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- /*
- * Copyright (C)2009-2015, 2017, 2020-2021 D. R. Commander.
- * All Rights Reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * - Redistributions of source code must retain the above copyright notice,
- * this list of conditions and the following disclaimer.
- * - Redistributions in binary form must reproduce the above copyright notice,
- * this list of conditions and the following disclaimer in the documentation
- * and/or other materials provided with the distribution.
- * - Neither the name of the libjpeg-turbo Project nor the names of its
- * contributors may be used to endorse or promote products derived from this
- * software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS",
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
- #ifndef __TURBOJPEG_H__
- #define __TURBOJPEG_H__
- #if defined(_WIN32) && defined(DLLDEFINE)
- #define DLLEXPORT __declspec(dllexport)
- #else
- #define DLLEXPORT
- #endif
- #define DLLCALL
- /**
- * @addtogroup TurboJPEG
- * TurboJPEG API. This API provides an interface for generating, decoding, and
- * transforming planar YUV and JPEG images in memory.
- *
- * @anchor YUVnotes
- * YUV Image Format Notes
- * ----------------------
- * Technically, the JPEG format uses the YCbCr colorspace (which is technically
- * not a colorspace but a color transform), but per the convention of the
- * digital video community, the TurboJPEG API uses "YUV" to refer to an image
- * format consisting of Y, Cb, and Cr image planes.
- *
- * Each plane is simply a 2D array of bytes, each byte representing the value
- * of one of the components (Y, Cb, or Cr) at a particular location in the
- * image. The width and height of each plane are determined by the image
- * width, height, and level of chrominance subsampling. The luminance plane
- * width is the image width padded to the nearest multiple of the horizontal
- * subsampling factor (2 in the case of 4:2:0 and 4:2:2, 4 in the case of
- * 4:1:1, 1 in the case of 4:4:4 or grayscale.) Similarly, the luminance plane
- * height is the image height padded to the nearest multiple of the vertical
- * subsampling factor (2 in the case of 4:2:0 or 4:4:0, 1 in the case of 4:4:4
- * or grayscale.) This is irrespective of any additional padding that may be
- * specified as an argument to the various YUV functions. The chrominance
- * plane width is equal to the luminance plane width divided by the horizontal
- * subsampling factor, and the chrominance plane height is equal to the
- * luminance plane height divided by the vertical subsampling factor.
- *
- * For example, if the source image is 35 x 35 pixels and 4:2:2 subsampling is
- * used, then the luminance plane would be 36 x 35 bytes, and each of the
- * chrominance planes would be 18 x 35 bytes. If you specify a line padding of
- * 4 bytes on top of this, then the luminance plane would be 36 x 35 bytes, and
- * each of the chrominance planes would be 20 x 35 bytes.
- *
- * @{
- */
- /**
- * The number of chrominance subsampling options
- */
- #define TJ_NUMSAMP 6
- /**
- * Chrominance subsampling options.
- * When pixels are converted from RGB to YCbCr (see #TJCS_YCbCr) or from CMYK
- * to YCCK (see #TJCS_YCCK) as part of the JPEG compression process, some of
- * the Cb and Cr (chrominance) components can be discarded or averaged together
- * to produce a smaller image with little perceptible loss of image clarity
- * (the human eye is more sensitive to small changes in brightness than to
- * small changes in color.) This is called "chrominance subsampling".
- */
- enum TJSAMP {
- /**
- * 4:4:4 chrominance subsampling (no chrominance subsampling). The JPEG or
- * YUV image will contain one chrominance component for every pixel in the
- * source image.
- */
- TJSAMP_444 = 0,
- /**
- * 4:2:2 chrominance subsampling. The JPEG or YUV image will contain one
- * chrominance component for every 2x1 block of pixels in the source image.
- */
- TJSAMP_422,
- /**
- * 4:2:0 chrominance subsampling. The JPEG or YUV image will contain one
- * chrominance component for every 2x2 block of pixels in the source image.
- */
- TJSAMP_420,
- /**
- * Grayscale. The JPEG or YUV image will contain no chrominance components.
- */
- TJSAMP_GRAY,
- /**
- * 4:4:0 chrominance subsampling. The JPEG or YUV image will contain one
- * chrominance component for every 1x2 block of pixels in the source image.
- *
- * @note 4:4:0 subsampling is not fully accelerated in libjpeg-turbo.
- */
- TJSAMP_440,
- /**
- * 4:1:1 chrominance subsampling. The JPEG or YUV image will contain one
- * chrominance component for every 4x1 block of pixels in the source image.
- * JPEG images compressed with 4:1:1 subsampling will be almost exactly the
- * same size as those compressed with 4:2:0 subsampling, and in the
- * aggregate, both subsampling methods produce approximately the same
- * perceptual quality. However, 4:1:1 is better able to reproduce sharp
- * horizontal features.
- *
- * @note 4:1:1 subsampling is not fully accelerated in libjpeg-turbo.
- */
- TJSAMP_411
- };
- /**
- * MCU block width (in pixels) for a given level of chrominance subsampling.
- * MCU block sizes:
- * - 8x8 for no subsampling or grayscale
- * - 16x8 for 4:2:2
- * - 8x16 for 4:4:0
- * - 16x16 for 4:2:0
- * - 32x8 for 4:1:1
- */
- static const int tjMCUWidth[TJ_NUMSAMP] = { 8, 16, 16, 8, 8, 32 };
- /**
- * MCU block height (in pixels) for a given level of chrominance subsampling.
- * MCU block sizes:
- * - 8x8 for no subsampling or grayscale
- * - 16x8 for 4:2:2
- * - 8x16 for 4:4:0
- * - 16x16 for 4:2:0
- * - 32x8 for 4:1:1
- */
- static const int tjMCUHeight[TJ_NUMSAMP] = { 8, 8, 16, 8, 16, 8 };
- /**
- * The number of pixel formats
- */
- #define TJ_NUMPF 12
- /**
- * Pixel formats
- */
- enum TJPF {
- /**
- * RGB pixel format. The red, green, and blue components in the image are
- * stored in 3-byte pixels in the order R, G, B from lowest to highest byte
- * address within each pixel.
- */
- TJPF_RGB = 0,
- /**
- * BGR pixel format. The red, green, and blue components in the image are
- * stored in 3-byte pixels in the order B, G, R from lowest to highest byte
- * address within each pixel.
- */
- TJPF_BGR,
- /**
- * RGBX pixel format. The red, green, and blue components in the image are
- * stored in 4-byte pixels in the order R, G, B from lowest to highest byte
- * address within each pixel. The X component is ignored when compressing
- * and undefined when decompressing.
- */
- TJPF_RGBX,
- /**
- * BGRX pixel format. The red, green, and blue components in the image are
- * stored in 4-byte pixels in the order B, G, R from lowest to highest byte
- * address within each pixel. The X component is ignored when compressing
- * and undefined when decompressing.
- */
- TJPF_BGRX,
- /**
- * XBGR pixel format. The red, green, and blue components in the image are
- * stored in 4-byte pixels in the order R, G, B from highest to lowest byte
- * address within each pixel. The X component is ignored when compressing
- * and undefined when decompressing.
- */
- TJPF_XBGR,
- /**
- * XRGB pixel format. The red, green, and blue components in the image are
- * stored in 4-byte pixels in the order B, G, R from highest to lowest byte
- * address within each pixel. The X component is ignored when compressing
- * and undefined when decompressing.
- */
- TJPF_XRGB,
- /**
- * Grayscale pixel format. Each 1-byte pixel represents a luminance
- * (brightness) level from 0 to 255.
- */
- TJPF_GRAY,
- /**
- * RGBA pixel format. This is the same as @ref TJPF_RGBX, except that when
- * decompressing, the X component is guaranteed to be 0xFF, which can be
- * interpreted as an opaque alpha channel.
- */
- TJPF_RGBA,
- /**
- * BGRA pixel format. This is the same as @ref TJPF_BGRX, except that when
- * decompressing, the X component is guaranteed to be 0xFF, which can be
- * interpreted as an opaque alpha channel.
- */
- TJPF_BGRA,
- /**
- * ABGR pixel format. This is the same as @ref TJPF_XBGR, except that when
- * decompressing, the X component is guaranteed to be 0xFF, which can be
- * interpreted as an opaque alpha channel.
- */
- TJPF_ABGR,
- /**
- * ARGB pixel format. This is the same as @ref TJPF_XRGB, except that when
- * decompressing, the X component is guaranteed to be 0xFF, which can be
- * interpreted as an opaque alpha channel.
- */
- TJPF_ARGB,
- /**
- * CMYK pixel format. Unlike RGB, which is an additive color model used
- * primarily for display, CMYK (Cyan/Magenta/Yellow/Key) is a subtractive
- * color model used primarily for printing. In the CMYK color model, the
- * value of each color component typically corresponds to an amount of cyan,
- * magenta, yellow, or black ink that is applied to a white background. In
- * order to convert between CMYK and RGB, it is necessary to use a color
- * management system (CMS.) A CMS will attempt to map colors within the
- * printer's gamut to perceptually similar colors in the display's gamut and
- * vice versa, but the mapping is typically not 1:1 or reversible, nor can it
- * be defined with a simple formula. Thus, such a conversion is out of scope
- * for a codec library. However, the TurboJPEG API allows for compressing
- * CMYK pixels into a YCCK JPEG image (see #TJCS_YCCK) and decompressing YCCK
- * JPEG images into CMYK pixels.
- */
- TJPF_CMYK,
- /**
- * Unknown pixel format. Currently this is only used by #tjLoadImage().
- */
- TJPF_UNKNOWN = -1
- };
- /**
- * Red offset (in bytes) for a given pixel format. This specifies the number
- * of bytes that the red component is offset from the start of the pixel. For
- * instance, if a pixel of format TJ_BGRX is stored in <tt>char pixel[]</tt>,
- * then the red component will be <tt>pixel[tjRedOffset[TJ_BGRX]]</tt>. This
- * will be -1 if the pixel format does not have a red component.
- */
- static const int tjRedOffset[TJ_NUMPF] = {
- 0, 2, 0, 2, 3, 1, -1, 0, 2, 3, 1, -1
- };
- /**
- * Green offset (in bytes) for a given pixel format. This specifies the number
- * of bytes that the green component is offset from the start of the pixel.
- * For instance, if a pixel of format TJ_BGRX is stored in
- * <tt>char pixel[]</tt>, then the green component will be
- * <tt>pixel[tjGreenOffset[TJ_BGRX]]</tt>. This will be -1 if the pixel format
- * does not have a green component.
- */
- static const int tjGreenOffset[TJ_NUMPF] = {
- 1, 1, 1, 1, 2, 2, -1, 1, 1, 2, 2, -1
- };
- /**
- * Blue offset (in bytes) for a given pixel format. This specifies the number
- * of bytes that the Blue component is offset from the start of the pixel. For
- * instance, if a pixel of format TJ_BGRX is stored in <tt>char pixel[]</tt>,
- * then the blue component will be <tt>pixel[tjBlueOffset[TJ_BGRX]]</tt>. This
- * will be -1 if the pixel format does not have a blue component.
- */
- static const int tjBlueOffset[TJ_NUMPF] = {
- 2, 0, 2, 0, 1, 3, -1, 2, 0, 1, 3, -1
- };
- /**
- * Alpha offset (in bytes) for a given pixel format. This specifies the number
- * of bytes that the Alpha component is offset from the start of the pixel.
- * For instance, if a pixel of format TJ_BGRA is stored in
- * <tt>char pixel[]</tt>, then the alpha component will be
- * <tt>pixel[tjAlphaOffset[TJ_BGRA]]</tt>. This will be -1 if the pixel format
- * does not have an alpha component.
- */
- static const int tjAlphaOffset[TJ_NUMPF] = {
- -1, -1, -1, -1, -1, -1, -1, 3, 3, 0, 0, -1
- };
- /**
- * Pixel size (in bytes) for a given pixel format
- */
- static const int tjPixelSize[TJ_NUMPF] = {
- 3, 3, 4, 4, 4, 4, 1, 4, 4, 4, 4, 4
- };
- /**
- * The number of JPEG colorspaces
- */
- #define TJ_NUMCS 5
- /**
- * JPEG colorspaces
- */
- enum TJCS {
- /**
- * RGB colorspace. When compressing the JPEG image, the R, G, and B
- * components in the source image are reordered into image planes, but no
- * colorspace conversion or subsampling is performed. RGB JPEG images can be
- * decompressed to any of the extended RGB pixel formats or grayscale, but
- * they cannot be decompressed to YUV images.
- */
- TJCS_RGB = 0,
- /**
- * YCbCr colorspace. YCbCr is not an absolute colorspace but rather a
- * mathematical transformation of RGB designed solely for storage and
- * transmission. YCbCr images must be converted to RGB before they can
- * actually be displayed. In the YCbCr colorspace, the Y (luminance)
- * component represents the black & white portion of the original image, and
- * the Cb and Cr (chrominance) components represent the color portion of the
- * original image. Originally, the analog equivalent of this transformation
- * allowed the same signal to drive both black & white and color televisions,
- * but JPEG images use YCbCr primarily because it allows the color data to be
- * optionally subsampled for the purposes of reducing bandwidth or disk
- * space. YCbCr is the most common JPEG colorspace, and YCbCr JPEG images
- * can be compressed from and decompressed to any of the extended RGB pixel
- * formats or grayscale, or they can be decompressed to YUV planar images.
- */
- TJCS_YCbCr,
- /**
- * Grayscale colorspace. The JPEG image retains only the luminance data (Y
- * component), and any color data from the source image is discarded.
- * Grayscale JPEG images can be compressed from and decompressed to any of
- * the extended RGB pixel formats or grayscale, or they can be decompressed
- * to YUV planar images.
- */
- TJCS_GRAY,
- /**
- * CMYK colorspace. When compressing the JPEG image, the C, M, Y, and K
- * components in the source image are reordered into image planes, but no
- * colorspace conversion or subsampling is performed. CMYK JPEG images can
- * only be decompressed to CMYK pixels.
- */
- TJCS_CMYK,
- /**
- * YCCK colorspace. YCCK (AKA "YCbCrK") is not an absolute colorspace but
- * rather a mathematical transformation of CMYK designed solely for storage
- * and transmission. It is to CMYK as YCbCr is to RGB. CMYK pixels can be
- * reversibly transformed into YCCK, and as with YCbCr, the chrominance
- * components in the YCCK pixels can be subsampled without incurring major
- * perceptual loss. YCCK JPEG images can only be compressed from and
- * decompressed to CMYK pixels.
- */
- TJCS_YCCK
- };
- /**
- * The uncompressed source/destination image is stored in bottom-up (Windows,
- * OpenGL) order, not top-down (X11) order.
- */
- #define TJFLAG_BOTTOMUP 2
- /**
- * When decompressing an image that was compressed using chrominance
- * subsampling, use the fastest chrominance upsampling algorithm available in
- * the underlying codec. The default is to use smooth upsampling, which
- * creates a smooth transition between neighboring chrominance components in
- * order to reduce upsampling artifacts in the decompressed image.
- */
- #define TJFLAG_FASTUPSAMPLE 256
- /**
- * Disable buffer (re)allocation. If passed to one of the JPEG compression or
- * transform functions, this flag will cause those functions to generate an
- * error if the JPEG image buffer is invalid or too small rather than
- * attempting to allocate or reallocate that buffer. This reproduces the
- * behavior of earlier versions of TurboJPEG.
- */
- #define TJFLAG_NOREALLOC 1024
- /**
- * Use the fastest DCT/IDCT algorithm available in the underlying codec. The
- * default if this flag is not specified is implementation-specific. For
- * example, the implementation of TurboJPEG for libjpeg[-turbo] uses the fast
- * algorithm by default when compressing, because this has been shown to have
- * only a very slight effect on accuracy, but it uses the accurate algorithm
- * when decompressing, because this has been shown to have a larger effect.
- */
- #define TJFLAG_FASTDCT 2048
- /**
- * Use the most accurate DCT/IDCT algorithm available in the underlying codec.
- * The default if this flag is not specified is implementation-specific. For
- * example, the implementation of TurboJPEG for libjpeg[-turbo] uses the fast
- * algorithm by default when compressing, because this has been shown to have
- * only a very slight effect on accuracy, but it uses the accurate algorithm
- * when decompressing, because this has been shown to have a larger effect.
- */
- #define TJFLAG_ACCURATEDCT 4096
- /**
- * Immediately discontinue the current compression/decompression/transform
- * operation if the underlying codec throws a warning (non-fatal error). The
- * default behavior is to allow the operation to complete unless a fatal error
- * is encountered.
- */
- #define TJFLAG_STOPONWARNING 8192
- /**
- * Use progressive entropy coding in JPEG images generated by the compression
- * and transform functions. Progressive entropy coding will generally improve
- * compression relative to baseline entropy coding (the default), but it will
- * reduce compression and decompression performance considerably.
- */
- #define TJFLAG_PROGRESSIVE 16384
- /**
- * Limit the number of progressive JPEG scans that the decompression and
- * transform functions will process. If a progressive JPEG image contains an
- * unreasonably large number of scans, then this flag will cause the
- * decompression and transform functions to return an error. The primary
- * purpose of this is to allow security-critical applications to guard against
- * an exploit of the progressive JPEG format described in
- * <a href="https://libjpeg-turbo.org/pmwiki/uploads/About/TwoIssueswiththeJPEGStandard.pdf" target="_blank">this report</a>.
- */
- #define TJFLAG_LIMITSCANS 32768
- /**
- * The number of error codes
- */
- #define TJ_NUMERR 2
- /**
- * Error codes
- */
- enum TJERR {
- /**
- * The error was non-fatal and recoverable, but the image may still be
- * corrupt.
- */
- TJERR_WARNING = 0,
- /**
- * The error was fatal and non-recoverable.
- */
- TJERR_FATAL
- };
- /**
- * The number of transform operations
- */
- #define TJ_NUMXOP 8
- /**
- * Transform operations for #tjTransform()
- */
- enum TJXOP {
- /**
- * Do not transform the position of the image pixels
- */
- TJXOP_NONE = 0,
- /**
- * Flip (mirror) image horizontally. This transform is imperfect if there
- * are any partial MCU blocks on the right edge (see #TJXOPT_PERFECT.)
- */
- TJXOP_HFLIP,
- /**
- * Flip (mirror) image vertically. This transform is imperfect if there are
- * any partial MCU blocks on the bottom edge (see #TJXOPT_PERFECT.)
- */
- TJXOP_VFLIP,
- /**
- * Transpose image (flip/mirror along upper left to lower right axis.) This
- * transform is always perfect.
- */
- TJXOP_TRANSPOSE,
- /**
- * Transverse transpose image (flip/mirror along upper right to lower left
- * axis.) This transform is imperfect if there are any partial MCU blocks in
- * the image (see #TJXOPT_PERFECT.)
- */
- TJXOP_TRANSVERSE,
- /**
- * Rotate image clockwise by 90 degrees. This transform is imperfect if
- * there are any partial MCU blocks on the bottom edge (see
- * #TJXOPT_PERFECT.)
- */
- TJXOP_ROT90,
- /**
- * Rotate image 180 degrees. This transform is imperfect if there are any
- * partial MCU blocks in the image (see #TJXOPT_PERFECT.)
- */
- TJXOP_ROT180,
- /**
- * Rotate image counter-clockwise by 90 degrees. This transform is imperfect
- * if there are any partial MCU blocks on the right edge (see
- * #TJXOPT_PERFECT.)
- */
- TJXOP_ROT270
- };
- /**
- * This option will cause #tjTransform() to return an error if the transform is
- * not perfect. Lossless transforms operate on MCU blocks, whose size depends
- * on the level of chrominance subsampling used (see #tjMCUWidth
- * and #tjMCUHeight.) If the image's width or height is not evenly divisible
- * by the MCU block size, then there will be partial MCU blocks on the right
- * and/or bottom edges. It is not possible to move these partial MCU blocks to
- * the top or left of the image, so any transform that would require that is
- * "imperfect." If this option is not specified, then any partial MCU blocks
- * that cannot be transformed will be left in place, which will create
- * odd-looking strips on the right or bottom edge of the image.
- */
- #define TJXOPT_PERFECT 1
- /**
- * This option will cause #tjTransform() to discard any partial MCU blocks that
- * cannot be transformed.
- */
- #define TJXOPT_TRIM 2
- /**
- * This option will enable lossless cropping. See #tjTransform() for more
- * information.
- */
- #define TJXOPT_CROP 4
- /**
- * This option will discard the color data in the input image and produce
- * a grayscale output image.
- */
- #define TJXOPT_GRAY 8
- /**
- * This option will prevent #tjTransform() from outputting a JPEG image for
- * this particular transform (this can be used in conjunction with a custom
- * filter to capture the transformed DCT coefficients without transcoding
- * them.)
- */
- #define TJXOPT_NOOUTPUT 16
- /**
- * This option will enable progressive entropy coding in the output image
- * generated by this particular transform. Progressive entropy coding will
- * generally improve compression relative to baseline entropy coding (the
- * default), but it will reduce compression and decompression performance
- * considerably.
- */
- #define TJXOPT_PROGRESSIVE 32
- /**
- * This option will prevent #tjTransform() from copying any extra markers
- * (including EXIF and ICC profile data) from the source image to the output
- * image.
- */
- #define TJXOPT_COPYNONE 64
- /**
- * Scaling factor
- */
- typedef struct {
- /**
- * Numerator
- */
- int num;
- /**
- * Denominator
- */
- int denom;
- } tjscalingfactor;
- /**
- * Cropping region
- */
- typedef struct {
- /**
- * The left boundary of the cropping region. This must be evenly divisible
- * by the MCU block width (see #tjMCUWidth.)
- */
- int x;
- /**
- * The upper boundary of the cropping region. This must be evenly divisible
- * by the MCU block height (see #tjMCUHeight.)
- */
- int y;
- /**
- * The width of the cropping region. Setting this to 0 is the equivalent of
- * setting it to the width of the source JPEG image - x.
- */
- int w;
- /**
- * The height of the cropping region. Setting this to 0 is the equivalent of
- * setting it to the height of the source JPEG image - y.
- */
- int h;
- } tjregion;
- /**
- * Lossless transform
- */
- typedef struct tjtransform {
- /**
- * Cropping region
- */
- tjregion r;
- /**
- * One of the @ref TJXOP "transform operations"
- */
- int op;
- /**
- * The bitwise OR of one of more of the @ref TJXOPT_CROP "transform options"
- */
- int options;
- /**
- * Arbitrary data that can be accessed within the body of the callback
- * function
- */
- void *data;
- /**
- * A callback function that can be used to modify the DCT coefficients
- * after they are losslessly transformed but before they are transcoded to a
- * new JPEG image. This allows for custom filters or other transformations
- * to be applied in the frequency domain.
- *
- * @param coeffs pointer to an array of transformed DCT coefficients. (NOTE:
- * this pointer is not guaranteed to be valid once the callback returns, so
- * applications wishing to hand off the DCT coefficients to another function
- * or library should make a copy of them within the body of the callback.)
- *
- * @param arrayRegion #tjregion structure containing the width and height of
- * the array pointed to by <tt>coeffs</tt> as well as its offset relative to
- * the component plane. TurboJPEG implementations may choose to split each
- * component plane into multiple DCT coefficient arrays and call the callback
- * function once for each array.
- *
- * @param planeRegion #tjregion structure containing the width and height of
- * the component plane to which <tt>coeffs</tt> belongs
- *
- * @param componentID ID number of the component plane to which
- * <tt>coeffs</tt> belongs (Y, Cb, and Cr have, respectively, ID's of 0, 1,
- * and 2 in typical JPEG images.)
- *
- * @param transformID ID number of the transformed image to which
- * <tt>coeffs</tt> belongs. This is the same as the index of the transform
- * in the <tt>transforms</tt> array that was passed to #tjTransform().
- *
- * @param transform a pointer to a #tjtransform structure that specifies the
- * parameters and/or cropping region for this transform
- *
- * @return 0 if the callback was successful, or -1 if an error occurred.
- */
- int (*customFilter) (short *coeffs, tjregion arrayRegion,
- tjregion planeRegion, int componentIndex,
- int transformIndex, struct tjtransform *transform);
- } tjtransform;
- /**
- * TurboJPEG instance handle
- */
- typedef void *tjhandle;
- /**
- * Pad the given width to the nearest 32-bit boundary
- */
- #define TJPAD(width) (((width) + 3) & (~3))
- /**
- * Compute the scaled value of <tt>dimension</tt> using the given scaling
- * factor. This macro performs the integer equivalent of <tt>ceil(dimension *
- * scalingFactor)</tt>.
- */
- #define TJSCALED(dimension, scalingFactor) \
- (((dimension) * scalingFactor.num + scalingFactor.denom - 1) / \
- scalingFactor.denom)
- #ifdef __cplusplus
- extern "C" {
- #endif
- /**
- * Create a TurboJPEG compressor instance.
- *
- * @return a handle to the newly-created instance, or NULL if an error
- * occurred (see #tjGetErrorStr2().)
- */
- DLLEXPORT tjhandle tjInitCompress(void);
- /**
- * Compress an RGB, grayscale, or CMYK image into a JPEG image.
- *
- * @param handle a handle to a TurboJPEG compressor or transformer instance
- *
- * @param srcBuf pointer to an image buffer containing RGB, grayscale, or
- * CMYK pixels to be compressed
- *
- * @param width width (in pixels) of the source image
- *
- * @param pitch bytes per line in the source image. Normally, this should be
- * <tt>width * #tjPixelSize[pixelFormat]</tt> if the image is unpadded, or
- * <tt>#TJPAD(width * #tjPixelSize[pixelFormat])</tt> if each line of the image
- * is padded to the nearest 32-bit boundary, as is the case for Windows
- * bitmaps. You can also be clever and use this parameter to skip lines, etc.
- * Setting this parameter to 0 is the equivalent of setting it to
- * <tt>width * #tjPixelSize[pixelFormat]</tt>.
- *
- * @param height height (in pixels) of the source image
- *
- * @param pixelFormat pixel format of the source image (see @ref TJPF
- * "Pixel formats".)
- *
- * @param jpegBuf address of a pointer to an image buffer that will receive the
- * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer
- * to accommodate the size of the JPEG image. Thus, you can choose to:
- * -# pre-allocate the JPEG buffer with an arbitrary size using #tjAlloc() and
- * let TurboJPEG grow the buffer as needed,
- * -# set <tt>*jpegBuf</tt> to NULL to tell TurboJPEG to allocate the buffer
- * for you, or
- * -# pre-allocate the buffer to a "worst case" size determined by calling
- * #tjBufSize(). This should ensure that the buffer never has to be
- * re-allocated (setting #TJFLAG_NOREALLOC guarantees that it won't be.)
- * .
- * If you choose option 1, <tt>*jpegSize</tt> should be set to the size of your
- * pre-allocated buffer. In any case, unless you have set #TJFLAG_NOREALLOC,
- * you should always check <tt>*jpegBuf</tt> upon return from this function, as
- * it may have changed.
- *
- * @param jpegSize pointer to an unsigned long variable that holds the size of
- * the JPEG image buffer. If <tt>*jpegBuf</tt> points to a pre-allocated
- * buffer, then <tt>*jpegSize</tt> should be set to the size of the buffer.
- * Upon return, <tt>*jpegSize</tt> will contain the size of the JPEG image (in
- * bytes.) If <tt>*jpegBuf</tt> points to a JPEG image buffer that is being
- * reused from a previous call to one of the JPEG compression functions, then
- * <tt>*jpegSize</tt> is ignored.
- *
- * @param jpegSubsamp the level of chrominance subsampling to be used when
- * generating the JPEG image (see @ref TJSAMP
- * "Chrominance subsampling options".)
- *
- * @param jpegQual the image quality of the generated JPEG image (1 = worst,
- * 100 = best)
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjCompress2(tjhandle handle, const unsigned char *srcBuf,
- int width, int pitch, int height, int pixelFormat,
- unsigned char **jpegBuf, unsigned long *jpegSize,
- int jpegSubsamp, int jpegQual, int flags);
- /**
- * Compress a YUV planar image into a JPEG image.
- *
- * @param handle a handle to a TurboJPEG compressor or transformer instance
- *
- * @param srcBuf pointer to an image buffer containing a YUV planar image to be
- * compressed. The size of this buffer should match the value returned by
- * #tjBufSizeYUV2() for the given image width, height, padding, and level of
- * chrominance subsampling. The Y, U (Cb), and V (Cr) image planes should be
- * stored sequentially in the source buffer (refer to @ref YUVnotes
- * "YUV Image Format Notes".)
- *
- * @param width width (in pixels) of the source image. If the width is not an
- * even multiple of the MCU block width (see #tjMCUWidth), then an intermediate
- * buffer copy will be performed within TurboJPEG.
- *
- * @param pad the line padding used in the source image. For instance, if each
- * line in each plane of the YUV image is padded to the nearest multiple of 4
- * bytes, then <tt>pad</tt> should be set to 4.
- *
- * @param height height (in pixels) of the source image. If the height is not
- * an even multiple of the MCU block height (see #tjMCUHeight), then an
- * intermediate buffer copy will be performed within TurboJPEG.
- *
- * @param subsamp the level of chrominance subsampling used in the source
- * image (see @ref TJSAMP "Chrominance subsampling options".)
- *
- * @param jpegBuf address of a pointer to an image buffer that will receive the
- * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to
- * accommodate the size of the JPEG image. Thus, you can choose to:
- * -# pre-allocate the JPEG buffer with an arbitrary size using #tjAlloc() and
- * let TurboJPEG grow the buffer as needed,
- * -# set <tt>*jpegBuf</tt> to NULL to tell TurboJPEG to allocate the buffer
- * for you, or
- * -# pre-allocate the buffer to a "worst case" size determined by calling
- * #tjBufSize(). This should ensure that the buffer never has to be
- * re-allocated (setting #TJFLAG_NOREALLOC guarantees that it won't be.)
- * .
- * If you choose option 1, <tt>*jpegSize</tt> should be set to the size of your
- * pre-allocated buffer. In any case, unless you have set #TJFLAG_NOREALLOC,
- * you should always check <tt>*jpegBuf</tt> upon return from this function, as
- * it may have changed.
- *
- * @param jpegSize pointer to an unsigned long variable that holds the size of
- * the JPEG image buffer. If <tt>*jpegBuf</tt> points to a pre-allocated
- * buffer, then <tt>*jpegSize</tt> should be set to the size of the buffer.
- * Upon return, <tt>*jpegSize</tt> will contain the size of the JPEG image (in
- * bytes.) If <tt>*jpegBuf</tt> points to a JPEG image buffer that is being
- * reused from a previous call to one of the JPEG compression functions, then
- * <tt>*jpegSize</tt> is ignored.
- *
- * @param jpegQual the image quality of the generated JPEG image (1 = worst,
- * 100 = best)
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjCompressFromYUV(tjhandle handle, const unsigned char *srcBuf,
- int width, int pad, int height, int subsamp,
- unsigned char **jpegBuf,
- unsigned long *jpegSize, int jpegQual,
- int flags);
- /**
- * Compress a set of Y, U (Cb), and V (Cr) image planes into a JPEG image.
- *
- * @param handle a handle to a TurboJPEG compressor or transformer instance
- *
- * @param srcPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes
- * (or just a Y plane, if compressing a grayscale image) that contain a YUV
- * image to be compressed. These planes can be contiguous or non-contiguous in
- * memory. The size of each plane should match the value returned by
- * #tjPlaneSizeYUV() for the given image width, height, strides, and level of
- * chrominance subsampling. Refer to @ref YUVnotes "YUV Image Format Notes"
- * for more details.
- *
- * @param width width (in pixels) of the source image. If the width is not an
- * even multiple of the MCU block width (see #tjMCUWidth), then an intermediate
- * buffer copy will be performed within TurboJPEG.
- *
- * @param strides an array of integers, each specifying the number of bytes per
- * line in the corresponding plane of the YUV source image. Setting the stride
- * for any plane to 0 is the same as setting it to the plane width (see
- * @ref YUVnotes "YUV Image Format Notes".) If <tt>strides</tt> is NULL, then
- * the strides for all planes will be set to their respective plane widths.
- * You can adjust the strides in order to specify an arbitrary amount of line
- * padding in each plane or to create a JPEG image from a subregion of a larger
- * YUV planar image.
- *
- * @param height height (in pixels) of the source image. If the height is not
- * an even multiple of the MCU block height (see #tjMCUHeight), then an
- * intermediate buffer copy will be performed within TurboJPEG.
- *
- * @param subsamp the level of chrominance subsampling used in the source
- * image (see @ref TJSAMP "Chrominance subsampling options".)
- *
- * @param jpegBuf address of a pointer to an image buffer that will receive the
- * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to
- * accommodate the size of the JPEG image. Thus, you can choose to:
- * -# pre-allocate the JPEG buffer with an arbitrary size using #tjAlloc() and
- * let TurboJPEG grow the buffer as needed,
- * -# set <tt>*jpegBuf</tt> to NULL to tell TurboJPEG to allocate the buffer
- * for you, or
- * -# pre-allocate the buffer to a "worst case" size determined by calling
- * #tjBufSize(). This should ensure that the buffer never has to be
- * re-allocated (setting #TJFLAG_NOREALLOC guarantees that it won't be.)
- * .
- * If you choose option 1, <tt>*jpegSize</tt> should be set to the size of your
- * pre-allocated buffer. In any case, unless you have set #TJFLAG_NOREALLOC,
- * you should always check <tt>*jpegBuf</tt> upon return from this function, as
- * it may have changed.
- *
- * @param jpegSize pointer to an unsigned long variable that holds the size of
- * the JPEG image buffer. If <tt>*jpegBuf</tt> points to a pre-allocated
- * buffer, then <tt>*jpegSize</tt> should be set to the size of the buffer.
- * Upon return, <tt>*jpegSize</tt> will contain the size of the JPEG image (in
- * bytes.) If <tt>*jpegBuf</tt> points to a JPEG image buffer that is being
- * reused from a previous call to one of the JPEG compression functions, then
- * <tt>*jpegSize</tt> is ignored.
- *
- * @param jpegQual the image quality of the generated JPEG image (1 = worst,
- * 100 = best)
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjCompressFromYUVPlanes(tjhandle handle,
- const unsigned char **srcPlanes,
- int width, const int *strides,
- int height, int subsamp,
- unsigned char **jpegBuf,
- unsigned long *jpegSize, int jpegQual,
- int flags);
- /**
- * The maximum size of the buffer (in bytes) required to hold a JPEG image with
- * the given parameters. The number of bytes returned by this function is
- * larger than the size of the uncompressed source image. The reason for this
- * is that the JPEG format uses 16-bit coefficients, and it is thus possible
- * for a very high-quality JPEG image with very high-frequency content to
- * expand rather than compress when converted to the JPEG format. Such images
- * represent a very rare corner case, but since there is no way to predict the
- * size of a JPEG image prior to compression, the corner case has to be
- * handled.
- *
- * @param width width (in pixels) of the image
- *
- * @param height height (in pixels) of the image
- *
- * @param jpegSubsamp the level of chrominance subsampling to be used when
- * generating the JPEG image (see @ref TJSAMP
- * "Chrominance subsampling options".)
- *
- * @return the maximum size of the buffer (in bytes) required to hold the
- * image, or -1 if the arguments are out of bounds.
- */
- DLLEXPORT unsigned long tjBufSize(int width, int height, int jpegSubsamp);
- /**
- * The size of the buffer (in bytes) required to hold a YUV planar image with
- * the given parameters.
- *
- * @param width width (in pixels) of the image
- *
- * @param pad the width of each line in each plane of the image is padded to
- * the nearest multiple of this number of bytes (must be a power of 2.)
- *
- * @param height height (in pixels) of the image
- *
- * @param subsamp level of chrominance subsampling in the image (see
- * @ref TJSAMP "Chrominance subsampling options".)
- *
- * @return the size of the buffer (in bytes) required to hold the image, or
- * -1 if the arguments are out of bounds.
- */
- DLLEXPORT unsigned long tjBufSizeYUV2(int width, int pad, int height,
- int subsamp);
- /**
- * The size of the buffer (in bytes) required to hold a YUV image plane with
- * the given parameters.
- *
- * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr)
- *
- * @param width width (in pixels) of the YUV image. NOTE: this is the width of
- * the whole image, not the plane width.
- *
- * @param stride bytes per line in the image plane. Setting this to 0 is the
- * equivalent of setting it to the plane width.
- *
- * @param height height (in pixels) of the YUV image. NOTE: this is the height
- * of the whole image, not the plane height.
- *
- * @param subsamp level of chrominance subsampling in the image (see
- * @ref TJSAMP "Chrominance subsampling options".)
- *
- * @return the size of the buffer (in bytes) required to hold the YUV image
- * plane, or -1 if the arguments are out of bounds.
- */
- DLLEXPORT unsigned long tjPlaneSizeYUV(int componentID, int width, int stride,
- int height, int subsamp);
- /**
- * The plane width of a YUV image plane with the given parameters. Refer to
- * @ref YUVnotes "YUV Image Format Notes" for a description of plane width.
- *
- * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr)
- *
- * @param width width (in pixels) of the YUV image
- *
- * @param subsamp level of chrominance subsampling in the image (see
- * @ref TJSAMP "Chrominance subsampling options".)
- *
- * @return the plane width of a YUV image plane with the given parameters, or
- * -1 if the arguments are out of bounds.
- */
- DLLEXPORT int tjPlaneWidth(int componentID, int width, int subsamp);
- /**
- * The plane height of a YUV image plane with the given parameters. Refer to
- * @ref YUVnotes "YUV Image Format Notes" for a description of plane height.
- *
- * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr)
- *
- * @param height height (in pixels) of the YUV image
- *
- * @param subsamp level of chrominance subsampling in the image (see
- * @ref TJSAMP "Chrominance subsampling options".)
- *
- * @return the plane height of a YUV image plane with the given parameters, or
- * -1 if the arguments are out of bounds.
- */
- DLLEXPORT int tjPlaneHeight(int componentID, int height, int subsamp);
- /**
- * Encode an RGB or grayscale image into a YUV planar image. This function
- * uses the accelerated color conversion routines in the underlying
- * codec but does not execute any of the other steps in the JPEG compression
- * process.
- *
- * @param handle a handle to a TurboJPEG compressor or transformer instance
- *
- * @param srcBuf pointer to an image buffer containing RGB or grayscale pixels
- * to be encoded
- *
- * @param width width (in pixels) of the source image
- *
- * @param pitch bytes per line in the source image. Normally, this should be
- * <tt>width * #tjPixelSize[pixelFormat]</tt> if the image is unpadded, or
- * <tt>#TJPAD(width * #tjPixelSize[pixelFormat])</tt> if each line of the image
- * is padded to the nearest 32-bit boundary, as is the case for Windows
- * bitmaps. You can also be clever and use this parameter to skip lines, etc.
- * Setting this parameter to 0 is the equivalent of setting it to
- * <tt>width * #tjPixelSize[pixelFormat]</tt>.
- *
- * @param height height (in pixels) of the source image
- *
- * @param pixelFormat pixel format of the source image (see @ref TJPF
- * "Pixel formats".)
- *
- * @param dstBuf pointer to an image buffer that will receive the YUV image.
- * Use #tjBufSizeYUV2() to determine the appropriate size for this buffer based
- * on the image width, height, padding, and level of chrominance subsampling.
- * The Y, U (Cb), and V (Cr) image planes will be stored sequentially in the
- * buffer (refer to @ref YUVnotes "YUV Image Format Notes".)
- *
- * @param pad the width of each line in each plane of the YUV image will be
- * padded to the nearest multiple of this number of bytes (must be a power of
- * 2.) To generate images suitable for X Video, <tt>pad</tt> should be set to
- * 4.
- *
- * @param subsamp the level of chrominance subsampling to be used when
- * generating the YUV image (see @ref TJSAMP
- * "Chrominance subsampling options".) To generate images suitable for X
- * Video, <tt>subsamp</tt> should be set to @ref TJSAMP_420. This produces an
- * image compatible with the I420 (AKA "YUV420P") format.
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjEncodeYUV3(tjhandle handle, const unsigned char *srcBuf,
- int width, int pitch, int height, int pixelFormat,
- unsigned char *dstBuf, int pad, int subsamp,
- int flags);
- /**
- * Encode an RGB or grayscale image into separate Y, U (Cb), and V (Cr) image
- * planes. This function uses the accelerated color conversion routines in the
- * underlying codec but does not execute any of the other steps in the JPEG
- * compression process.
- *
- * @param handle a handle to a TurboJPEG compressor or transformer instance
- *
- * @param srcBuf pointer to an image buffer containing RGB or grayscale pixels
- * to be encoded
- *
- * @param width width (in pixels) of the source image
- *
- * @param pitch bytes per line in the source image. Normally, this should be
- * <tt>width * #tjPixelSize[pixelFormat]</tt> if the image is unpadded, or
- * <tt>#TJPAD(width * #tjPixelSize[pixelFormat])</tt> if each line of the image
- * is padded to the nearest 32-bit boundary, as is the case for Windows
- * bitmaps. You can also be clever and use this parameter to skip lines, etc.
- * Setting this parameter to 0 is the equivalent of setting it to
- * <tt>width * #tjPixelSize[pixelFormat]</tt>.
- *
- * @param height height (in pixels) of the source image
- *
- * @param pixelFormat pixel format of the source image (see @ref TJPF
- * "Pixel formats".)
- *
- * @param dstPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes
- * (or just a Y plane, if generating a grayscale image) that will receive the
- * encoded image. These planes can be contiguous or non-contiguous in memory.
- * Use #tjPlaneSizeYUV() to determine the appropriate size for each plane based
- * on the image width, height, strides, and level of chrominance subsampling.
- * Refer to @ref YUVnotes "YUV Image Format Notes" for more details.
- *
- * @param strides an array of integers, each specifying the number of bytes per
- * line in the corresponding plane of the output image. Setting the stride for
- * any plane to 0 is the same as setting it to the plane width (see
- * @ref YUVnotes "YUV Image Format Notes".) If <tt>strides</tt> is NULL, then
- * the strides for all planes will be set to their respective plane widths.
- * You can adjust the strides in order to add an arbitrary amount of line
- * padding to each plane or to encode an RGB or grayscale image into a
- * subregion of a larger YUV planar image.
- *
- * @param subsamp the level of chrominance subsampling to be used when
- * generating the YUV image (see @ref TJSAMP
- * "Chrominance subsampling options".) To generate images suitable for X
- * Video, <tt>subsamp</tt> should be set to @ref TJSAMP_420. This produces an
- * image compatible with the I420 (AKA "YUV420P") format.
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjEncodeYUVPlanes(tjhandle handle, const unsigned char *srcBuf,
- int width, int pitch, int height,
- int pixelFormat, unsigned char **dstPlanes,
- int *strides, int subsamp, int flags);
- /**
- * Create a TurboJPEG decompressor instance.
- *
- * @return a handle to the newly-created instance, or NULL if an error
- * occurred (see #tjGetErrorStr2().)
- */
- DLLEXPORT tjhandle tjInitDecompress(void);
- /**
- * Retrieve information about a JPEG image without decompressing it, or prime
- * the decompressor with quantization and Huffman tables.
- *
- * @param handle a handle to a TurboJPEG decompressor or transformer instance
- *
- * @param jpegBuf pointer to a buffer containing a JPEG image or an
- * "abbreviated table specification" (AKA "tables-only") datastream. Passing a
- * tables-only datastream to this function primes the decompressor with
- * quantization and Huffman tables that can be used when decompressing
- * subsequent "abbreviated image" datastreams. This is useful, for instance,
- * when decompressing video streams in which all frames share the same
- * quantization and Huffman tables.
- *
- * @param jpegSize size of the JPEG image or tables-only datastream (in bytes)
- *
- * @param width pointer to an integer variable that will receive the width (in
- * pixels) of the JPEG image. If <tt>jpegBuf</tt> points to a tables-only
- * datastream, then <tt>width</tt> is ignored.
- *
- * @param height pointer to an integer variable that will receive the height
- * (in pixels) of the JPEG image. If <tt>jpegBuf</tt> points to a tables-only
- * datastream, then <tt>height</tt> is ignored.
- *
- * @param jpegSubsamp pointer to an integer variable that will receive the
- * level of chrominance subsampling used when the JPEG image was compressed
- * (see @ref TJSAMP "Chrominance subsampling options".) If <tt>jpegBuf</tt>
- * points to a tables-only datastream, then <tt>jpegSubsamp</tt> is ignored.
- *
- * @param jpegColorspace pointer to an integer variable that will receive one
- * of the JPEG colorspace constants, indicating the colorspace of the JPEG
- * image (see @ref TJCS "JPEG colorspaces".) If <tt>jpegBuf</tt>
- * points to a tables-only datastream, then <tt>jpegColorspace</tt> is ignored.
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjDecompressHeader3(tjhandle handle,
- const unsigned char *jpegBuf,
- unsigned long jpegSize, int *width,
- int *height, int *jpegSubsamp,
- int *jpegColorspace);
- /**
- * Returns a list of fractional scaling factors that the JPEG decompressor in
- * this implementation of TurboJPEG supports.
- *
- * @param numscalingfactors pointer to an integer variable that will receive
- * the number of elements in the list
- *
- * @return a pointer to a list of fractional scaling factors, or NULL if an
- * error is encountered (see #tjGetErrorStr2().)
- */
- DLLEXPORT tjscalingfactor *tjGetScalingFactors(int *numscalingfactors);
- /**
- * Decompress a JPEG image to an RGB, grayscale, or CMYK image.
- *
- * @param handle a handle to a TurboJPEG decompressor or transformer instance
- *
- * @param jpegBuf pointer to a buffer containing the JPEG image to decompress
- *
- * @param jpegSize size of the JPEG image (in bytes)
- *
- * @param dstBuf pointer to an image buffer that will receive the decompressed
- * image. This buffer should normally be <tt>pitch * scaledHeight</tt> bytes
- * in size, where <tt>scaledHeight</tt> can be determined by calling
- * #TJSCALED() with the JPEG image height and one of the scaling factors
- * returned by #tjGetScalingFactors(). The <tt>dstBuf</tt> pointer may also be
- * used to decompress into a specific region of a larger buffer.
- *
- * @param width desired width (in pixels) of the destination image. If this is
- * different than the width of the JPEG image being decompressed, then
- * TurboJPEG will use scaling in the JPEG decompressor to generate the largest
- * possible image that will fit within the desired width. If <tt>width</tt> is
- * set to 0, then only the height will be considered when determining the
- * scaled image size.
- *
- * @param pitch bytes per line in the destination image. Normally, this is
- * <tt>scaledWidth * #tjPixelSize[pixelFormat]</tt> if the decompressed image
- * is unpadded, else <tt>#TJPAD(scaledWidth * #tjPixelSize[pixelFormat])</tt>
- * if each line of the decompressed image is padded to the nearest 32-bit
- * boundary, as is the case for Windows bitmaps. (NOTE: <tt>scaledWidth</tt>
- * can be determined by calling #TJSCALED() with the JPEG image width and one
- * of the scaling factors returned by #tjGetScalingFactors().) You can also be
- * clever and use the pitch parameter to skip lines, etc. Setting this
- * parameter to 0 is the equivalent of setting it to
- * <tt>scaledWidth * #tjPixelSize[pixelFormat]</tt>.
- *
- * @param height desired height (in pixels) of the destination image. If this
- * is different than the height of the JPEG image being decompressed, then
- * TurboJPEG will use scaling in the JPEG decompressor to generate the largest
- * possible image that will fit within the desired height. If <tt>height</tt>
- * is set to 0, then only the width will be considered when determining the
- * scaled image size.
- *
- * @param pixelFormat pixel format of the destination image (see @ref
- * TJPF "Pixel formats".)
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjDecompress2(tjhandle handle, const unsigned char *jpegBuf,
- unsigned long jpegSize, unsigned char *dstBuf,
- int width, int pitch, int height, int pixelFormat,
- int flags);
- /**
- * Decompress a JPEG image to a YUV planar image. This function performs JPEG
- * decompression but leaves out the color conversion step, so a planar YUV
- * image is generated instead of an RGB image.
- *
- * @param handle a handle to a TurboJPEG decompressor or transformer instance
- *
- * @param jpegBuf pointer to a buffer containing the JPEG image to decompress
- *
- * @param jpegSize size of the JPEG image (in bytes)
- *
- * @param dstBuf pointer to an image buffer that will receive the YUV image.
- * Use #tjBufSizeYUV2() to determine the appropriate size for this buffer based
- * on the image width, height, padding, and level of subsampling. The Y,
- * U (Cb), and V (Cr) image planes will be stored sequentially in the buffer
- * (refer to @ref YUVnotes "YUV Image Format Notes".)
- *
- * @param width desired width (in pixels) of the YUV image. If this is
- * different than the width of the JPEG image being decompressed, then
- * TurboJPEG will use scaling in the JPEG decompressor to generate the largest
- * possible image that will fit within the desired width. If <tt>width</tt> is
- * set to 0, then only the height will be considered when determining the
- * scaled image size. If the scaled width is not an even multiple of the MCU
- * block width (see #tjMCUWidth), then an intermediate buffer copy will be
- * performed within TurboJPEG.
- *
- * @param pad the width of each line in each plane of the YUV image will be
- * padded to the nearest multiple of this number of bytes (must be a power of
- * 2.) To generate images suitable for X Video, <tt>pad</tt> should be set to
- * 4.
- *
- * @param height desired height (in pixels) of the YUV image. If this is
- * different than the height of the JPEG image being decompressed, then
- * TurboJPEG will use scaling in the JPEG decompressor to generate the largest
- * possible image that will fit within the desired height. If <tt>height</tt>
- * is set to 0, then only the width will be considered when determining the
- * scaled image size. If the scaled height is not an even multiple of the MCU
- * block height (see #tjMCUHeight), then an intermediate buffer copy will be
- * performed within TurboJPEG.
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjDecompressToYUV2(tjhandle handle, const unsigned char *jpegBuf,
- unsigned long jpegSize, unsigned char *dstBuf,
- int width, int pad, int height, int flags);
- /**
- * Decompress a JPEG image into separate Y, U (Cb), and V (Cr) image
- * planes. This function performs JPEG decompression but leaves out the color
- * conversion step, so a planar YUV image is generated instead of an RGB image.
- *
- * @param handle a handle to a TurboJPEG decompressor or transformer instance
- *
- * @param jpegBuf pointer to a buffer containing the JPEG image to decompress
- *
- * @param jpegSize size of the JPEG image (in bytes)
- *
- * @param dstPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes
- * (or just a Y plane, if decompressing a grayscale image) that will receive
- * the YUV image. These planes can be contiguous or non-contiguous in memory.
- * Use #tjPlaneSizeYUV() to determine the appropriate size for each plane based
- * on the scaled image width, scaled image height, strides, and level of
- * chrominance subsampling. Refer to @ref YUVnotes "YUV Image Format Notes"
- * for more details.
- *
- * @param width desired width (in pixels) of the YUV image. If this is
- * different than the width of the JPEG image being decompressed, then
- * TurboJPEG will use scaling in the JPEG decompressor to generate the largest
- * possible image that will fit within the desired width. If <tt>width</tt> is
- * set to 0, then only the height will be considered when determining the
- * scaled image size. If the scaled width is not an even multiple of the MCU
- * block width (see #tjMCUWidth), then an intermediate buffer copy will be
- * performed within TurboJPEG.
- *
- * @param strides an array of integers, each specifying the number of bytes per
- * line in the corresponding plane of the output image. Setting the stride for
- * any plane to 0 is the same as setting it to the scaled plane width (see
- * @ref YUVnotes "YUV Image Format Notes".) If <tt>strides</tt> is NULL, then
- * the strides for all planes will be set to their respective scaled plane
- * widths. You can adjust the strides in order to add an arbitrary amount of
- * line padding to each plane or to decompress the JPEG image into a subregion
- * of a larger YUV planar image.
- *
- * @param height desired height (in pixels) of the YUV image. If this is
- * different than the height of the JPEG image being decompressed, then
- * TurboJPEG will use scaling in the JPEG decompressor to generate the largest
- * possible image that will fit within the desired height. If <tt>height</tt>
- * is set to 0, then only the width will be considered when determining the
- * scaled image size. If the scaled height is not an even multiple of the MCU
- * block height (see #tjMCUHeight), then an intermediate buffer copy will be
- * performed within TurboJPEG.
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjDecompressToYUVPlanes(tjhandle handle,
- const unsigned char *jpegBuf,
- unsigned long jpegSize,
- unsigned char **dstPlanes, int width,
- int *strides, int height, int flags);
- /**
- * Decode a YUV planar image into an RGB or grayscale image. This function
- * uses the accelerated color conversion routines in the underlying
- * codec but does not execute any of the other steps in the JPEG decompression
- * process.
- *
- * @param handle a handle to a TurboJPEG decompressor or transformer instance
- *
- * @param srcBuf pointer to an image buffer containing a YUV planar image to be
- * decoded. The size of this buffer should match the value returned by
- * #tjBufSizeYUV2() for the given image width, height, padding, and level of
- * chrominance subsampling. The Y, U (Cb), and V (Cr) image planes should be
- * stored sequentially in the source buffer (refer to @ref YUVnotes
- * "YUV Image Format Notes".)
- *
- * @param pad Use this parameter to specify that the width of each line in each
- * plane of the YUV source image is padded to the nearest multiple of this
- * number of bytes (must be a power of 2.)
- *
- * @param subsamp the level of chrominance subsampling used in the YUV source
- * image (see @ref TJSAMP "Chrominance subsampling options".)
- *
- * @param dstBuf pointer to an image buffer that will receive the decoded
- * image. This buffer should normally be <tt>pitch * height</tt> bytes in
- * size, but the <tt>dstBuf</tt> pointer can also be used to decode into a
- * specific region of a larger buffer.
- *
- * @param width width (in pixels) of the source and destination images
- *
- * @param pitch bytes per line in the destination image. Normally, this should
- * be <tt>width * #tjPixelSize[pixelFormat]</tt> if the destination image is
- * unpadded, or <tt>#TJPAD(width * #tjPixelSize[pixelFormat])</tt> if each line
- * of the destination image should be padded to the nearest 32-bit boundary, as
- * is the case for Windows bitmaps. You can also be clever and use the pitch
- * parameter to skip lines, etc. Setting this parameter to 0 is the equivalent
- * of setting it to <tt>width * #tjPixelSize[pixelFormat]</tt>.
- *
- * @param height height (in pixels) of the source and destination images
- *
- * @param pixelFormat pixel format of the destination image (see @ref TJPF
- * "Pixel formats".)
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjDecodeYUV(tjhandle handle, const unsigned char *srcBuf,
- int pad, int subsamp, unsigned char *dstBuf,
- int width, int pitch, int height, int pixelFormat,
- int flags);
- /**
- * Decode a set of Y, U (Cb), and V (Cr) image planes into an RGB or grayscale
- * image. This function uses the accelerated color conversion routines in the
- * underlying codec but does not execute any of the other steps in the JPEG
- * decompression process.
- *
- * @param handle a handle to a TurboJPEG decompressor or transformer instance
- *
- * @param srcPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes
- * (or just a Y plane, if decoding a grayscale image) that contain a YUV image
- * to be decoded. These planes can be contiguous or non-contiguous in memory.
- * The size of each plane should match the value returned by #tjPlaneSizeYUV()
- * for the given image width, height, strides, and level of chrominance
- * subsampling. Refer to @ref YUVnotes "YUV Image Format Notes" for more
- * details.
- *
- * @param strides an array of integers, each specifying the number of bytes per
- * line in the corresponding plane of the YUV source image. Setting the stride
- * for any plane to 0 is the same as setting it to the plane width (see
- * @ref YUVnotes "YUV Image Format Notes".) If <tt>strides</tt> is NULL, then
- * the strides for all planes will be set to their respective plane widths.
- * You can adjust the strides in order to specify an arbitrary amount of line
- * padding in each plane or to decode a subregion of a larger YUV planar image.
- *
- * @param subsamp the level of chrominance subsampling used in the YUV source
- * image (see @ref TJSAMP "Chrominance subsampling options".)
- *
- * @param dstBuf pointer to an image buffer that will receive the decoded
- * image. This buffer should normally be <tt>pitch * height</tt> bytes in
- * size, but the <tt>dstBuf</tt> pointer can also be used to decode into a
- * specific region of a larger buffer.
- *
- * @param width width (in pixels) of the source and destination images
- *
- * @param pitch bytes per line in the destination image. Normally, this should
- * be <tt>width * #tjPixelSize[pixelFormat]</tt> if the destination image is
- * unpadded, or <tt>#TJPAD(width * #tjPixelSize[pixelFormat])</tt> if each line
- * of the destination image should be padded to the nearest 32-bit boundary, as
- * is the case for Windows bitmaps. You can also be clever and use the pitch
- * parameter to skip lines, etc. Setting this parameter to 0 is the equivalent
- * of setting it to <tt>width * #tjPixelSize[pixelFormat]</tt>.
- *
- * @param height height (in pixels) of the source and destination images
- *
- * @param pixelFormat pixel format of the destination image (see @ref TJPF
- * "Pixel formats".)
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjDecodeYUVPlanes(tjhandle handle,
- const unsigned char **srcPlanes,
- const int *strides, int subsamp,
- unsigned char *dstBuf, int width, int pitch,
- int height, int pixelFormat, int flags);
- /**
- * Create a new TurboJPEG transformer instance.
- *
- * @return a handle to the newly-created instance, or NULL if an error
- * occurred (see #tjGetErrorStr2().)
- */
- DLLEXPORT tjhandle tjInitTransform(void);
- /**
- * Losslessly transform a JPEG image into another JPEG image. Lossless
- * transforms work by moving the raw DCT coefficients from one JPEG image
- * structure to another without altering the values of the coefficients. While
- * this is typically faster than decompressing the image, transforming it, and
- * re-compressing it, lossless transforms are not free. Each lossless
- * transform requires reading and performing Huffman decoding on all of the
- * coefficients in the source image, regardless of the size of the destination
- * image. Thus, this function provides a means of generating multiple
- * transformed images from the same source or applying multiple
- * transformations simultaneously, in order to eliminate the need to read the
- * source coefficients multiple times.
- *
- * @param handle a handle to a TurboJPEG transformer instance
- *
- * @param jpegBuf pointer to a buffer containing the JPEG source image to
- * transform
- *
- * @param jpegSize size of the JPEG source image (in bytes)
- *
- * @param n the number of transformed JPEG images to generate
- *
- * @param dstBufs pointer to an array of n image buffers. <tt>dstBufs[i]</tt>
- * will receive a JPEG image that has been transformed using the parameters in
- * <tt>transforms[i]</tt>. TurboJPEG has the ability to reallocate the JPEG
- * buffer to accommodate the size of the JPEG image. Thus, you can choose to:
- * -# pre-allocate the JPEG buffer with an arbitrary size using #tjAlloc() and
- * let TurboJPEG grow the buffer as needed,
- * -# set <tt>dstBufs[i]</tt> to NULL to tell TurboJPEG to allocate the buffer
- * for you, or
- * -# pre-allocate the buffer to a "worst case" size determined by calling
- * #tjBufSize() with the transformed or cropped width and height. Under normal
- * circumstances, this should ensure that the buffer never has to be
- * re-allocated (setting #TJFLAG_NOREALLOC guarantees that it won't be.) Note,
- * however, that there are some rare cases (such as transforming images with a
- * large amount of embedded EXIF or ICC profile data) in which the output image
- * will be larger than the worst-case size, and #TJFLAG_NOREALLOC cannot be
- * used in those cases.
- * .
- * If you choose option 1, <tt>dstSizes[i]</tt> should be set to the size of
- * your pre-allocated buffer. In any case, unless you have set
- * #TJFLAG_NOREALLOC, you should always check <tt>dstBufs[i]</tt> upon return
- * from this function, as it may have changed.
- *
- * @param dstSizes pointer to an array of n unsigned long variables that will
- * receive the actual sizes (in bytes) of each transformed JPEG image. If
- * <tt>dstBufs[i]</tt> points to a pre-allocated buffer, then
- * <tt>dstSizes[i]</tt> should be set to the size of the buffer. Upon return,
- * <tt>dstSizes[i]</tt> will contain the size of the JPEG image (in bytes.)
- *
- * @param transforms pointer to an array of n #tjtransform structures, each of
- * which specifies the transform parameters and/or cropping region for the
- * corresponding transformed output image.
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_ACCURATEDCT
- * "flags"
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2()
- * and #tjGetErrorCode().)
- */
- DLLEXPORT int tjTransform(tjhandle handle, const unsigned char *jpegBuf,
- unsigned long jpegSize, int n,
- unsigned char **dstBufs, unsigned long *dstSizes,
- tjtransform *transforms, int flags);
- /**
- * Destroy a TurboJPEG compressor, decompressor, or transformer instance.
- *
- * @param handle a handle to a TurboJPEG compressor, decompressor or
- * transformer instance
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2().)
- */
- DLLEXPORT int tjDestroy(tjhandle handle);
- /**
- * Allocate an image buffer for use with TurboJPEG. You should always use
- * this function to allocate the JPEG destination buffer(s) for the compression
- * and transform functions unless you are disabling automatic buffer
- * (re)allocation (by setting #TJFLAG_NOREALLOC.)
- *
- * @param bytes the number of bytes to allocate
- *
- * @return a pointer to a newly-allocated buffer with the specified number of
- * bytes.
- *
- * @sa tjFree()
- */
- DLLEXPORT unsigned char *tjAlloc(int bytes);
- /**
- * Load an uncompressed image from disk into memory.
- *
- * @param filename name of a file containing an uncompressed image in Windows
- * BMP or PBMPLUS (PPM/PGM) format
- *
- * @param width pointer to an integer variable that will receive the width (in
- * pixels) of the uncompressed image
- *
- * @param align row alignment of the image buffer to be returned (must be a
- * power of 2.) For instance, setting this parameter to 4 will cause all rows
- * in the image buffer to be padded to the nearest 32-bit boundary, and setting
- * this parameter to 1 will cause all rows in the image buffer to be unpadded.
- *
- * @param height pointer to an integer variable that will receive the height
- * (in pixels) of the uncompressed image
- *
- * @param pixelFormat pointer to an integer variable that specifies or will
- * receive the pixel format of the uncompressed image buffer. The behavior of
- * #tjLoadImage() will vary depending on the value of <tt>*pixelFormat</tt>
- * passed to the function:
- * - @ref TJPF_UNKNOWN : The uncompressed image buffer returned by the function
- * will use the most optimal pixel format for the file type, and
- * <tt>*pixelFormat</tt> will contain the ID of this pixel format upon
- * successful return from the function.
- * - @ref TJPF_GRAY : Only PGM files and 8-bit BMP files with a grayscale
- * colormap can be loaded.
- * - @ref TJPF_CMYK : The RGB or grayscale pixels stored in the file will be
- * converted using a quick & dirty algorithm that is suitable only for testing
- * purposes (proper conversion between CMYK and other formats requires a color
- * management system.)
- * - Other @ref TJPF "pixel formats" : The uncompressed image buffer will use
- * the specified pixel format, and pixel format conversion will be performed if
- * necessary.
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_BOTTOMUP
- * "flags".
- *
- * @return a pointer to a newly-allocated buffer containing the uncompressed
- * image, converted to the chosen pixel format and with the chosen row
- * alignment, or NULL if an error occurred (see #tjGetErrorStr2().) This
- * buffer should be freed using #tjFree().
- */
- DLLEXPORT unsigned char *tjLoadImage(const char *filename, int *width,
- int align, int *height, int *pixelFormat,
- int flags);
- /**
- * Save an uncompressed image from memory to disk.
- *
- * @param filename name of a file to which to save the uncompressed image.
- * The image will be stored in Windows BMP or PBMPLUS (PPM/PGM) format,
- * depending on the file extension.
- *
- * @param buffer pointer to an image buffer containing RGB, grayscale, or
- * CMYK pixels to be saved
- *
- * @param width width (in pixels) of the uncompressed image
- *
- * @param pitch bytes per line in the image buffer. Setting this parameter to
- * 0 is the equivalent of setting it to
- * <tt>width * #tjPixelSize[pixelFormat]</tt>.
- *
- * @param height height (in pixels) of the uncompressed image
- *
- * @param pixelFormat pixel format of the image buffer (see @ref TJPF
- * "Pixel formats".) If this parameter is set to @ref TJPF_GRAY, then the
- * image will be stored in PGM or 8-bit (indexed color) BMP format. Otherwise,
- * the image will be stored in PPM or 24-bit BMP format. If this parameter
- * is set to @ref TJPF_CMYK, then the CMYK pixels will be converted to RGB
- * using a quick & dirty algorithm that is suitable only for testing (proper
- * conversion between CMYK and other formats requires a color management
- * system.)
- *
- * @param flags the bitwise OR of one or more of the @ref TJFLAG_BOTTOMUP
- * "flags".
- *
- * @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr2().)
- */
- DLLEXPORT int tjSaveImage(const char *filename, unsigned char *buffer,
- int width, int pitch, int height, int pixelFormat,
- int flags);
- /**
- * Free an image buffer previously allocated by TurboJPEG. You should always
- * use this function to free JPEG destination buffer(s) that were automatically
- * (re)allocated by the compression and transform functions or that were
- * manually allocated using #tjAlloc().
- *
- * @param buffer address of the buffer to free. If the address is NULL, then
- * this function has no effect.
- *
- * @sa tjAlloc()
- */
- DLLEXPORT void tjFree(unsigned char *buffer);
- /**
- * Returns a descriptive error message explaining why the last command failed.
- *
- * @param handle a handle to a TurboJPEG compressor, decompressor, or
- * transformer instance, or NULL if the error was generated by a global
- * function (but note that retrieving the error message for a global function
- * is thread-safe only on platforms that support thread-local storage.)
- *
- * @return a descriptive error message explaining why the last command failed.
- */
- DLLEXPORT char *tjGetErrorStr2(tjhandle handle);
- /**
- * Returns a code indicating the severity of the last error. See
- * @ref TJERR "Error codes".
- *
- * @param handle a handle to a TurboJPEG compressor, decompressor or
- * transformer instance
- *
- * @return a code indicating the severity of the last error. See
- * @ref TJERR "Error codes".
- */
- DLLEXPORT int tjGetErrorCode(tjhandle handle);
- /* Deprecated functions and macros */
- #define TJFLAG_FORCEMMX 8
- #define TJFLAG_FORCESSE 16
- #define TJFLAG_FORCESSE2 32
- #define TJFLAG_FORCESSE3 128
- /* Backward compatibility functions and macros (nothing to see here) */
- #define NUMSUBOPT TJ_NUMSAMP
- #define TJ_444 TJSAMP_444
- #define TJ_422 TJSAMP_422
- #define TJ_420 TJSAMP_420
- #define TJ_411 TJSAMP_420
- #define TJ_GRAYSCALE TJSAMP_GRAY
- #define TJ_BGR 1
- #define TJ_BOTTOMUP TJFLAG_BOTTOMUP
- #define TJ_FORCEMMX TJFLAG_FORCEMMX
- #define TJ_FORCESSE TJFLAG_FORCESSE
- #define TJ_FORCESSE2 TJFLAG_FORCESSE2
- #define TJ_ALPHAFIRST 64
- #define TJ_FORCESSE3 TJFLAG_FORCESSE3
- #define TJ_FASTUPSAMPLE TJFLAG_FASTUPSAMPLE
- #define TJ_YUV 512
- DLLEXPORT unsigned long TJBUFSIZE(int width, int height);
- DLLEXPORT unsigned long TJBUFSIZEYUV(int width, int height, int jpegSubsamp);
- DLLEXPORT unsigned long tjBufSizeYUV(int width, int height, int subsamp);
- DLLEXPORT int tjCompress(tjhandle handle, unsigned char *srcBuf, int width,
- int pitch, int height, int pixelSize,
- unsigned char *dstBuf, unsigned long *compressedSize,
- int jpegSubsamp, int jpegQual, int flags);
- DLLEXPORT int tjEncodeYUV(tjhandle handle, unsigned char *srcBuf, int width,
- int pitch, int height, int pixelSize,
- unsigned char *dstBuf, int subsamp, int flags);
- DLLEXPORT int tjEncodeYUV2(tjhandle handle, unsigned char *srcBuf, int width,
- int pitch, int height, int pixelFormat,
- unsigned char *dstBuf, int subsamp, int flags);
- DLLEXPORT int tjDecompressHeader(tjhandle handle, unsigned char *jpegBuf,
- unsigned long jpegSize, int *width,
- int *height);
- DLLEXPORT int tjDecompressHeader2(tjhandle handle, unsigned char *jpegBuf,
- unsigned long jpegSize, int *width,
- int *height, int *jpegSubsamp);
- DLLEXPORT int tjDecompress(tjhandle handle, unsigned char *jpegBuf,
- unsigned long jpegSize, unsigned char *dstBuf,
- int width, int pitch, int height, int pixelSize,
- int flags);
- DLLEXPORT int tjDecompressToYUV(tjhandle handle, unsigned char *jpegBuf,
- unsigned long jpegSize, unsigned char *dstBuf,
- int flags);
- DLLEXPORT char *tjGetErrorStr(void);
- /**
- * @}
- */
- #ifdef __cplusplus
- }
- #endif
- #endif
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