Add pad filter.

Originally committed as revision 23046 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavfilter/Makefile

@@ -19,6 +19,7 @@ OBJS-$(CONFIG_CROP_FILTER)                   += vf_crop.o
 OBJS-$(CONFIG_FORMAT_FILTER)                 += vf_format.o
 OBJS-$(CONFIG_NOFORMAT_FILTER)               += vf_format.o
 OBJS-$(CONFIG_NULL_FILTER)                   += vf_null.o
+OBJS-$(CONFIG_PAD_FILTER)                    += vf_pad.o
 OBJS-$(CONFIG_PIXELASPECT_FILTER)            += vf_aspect.o
 OBJS-$(CONFIG_SCALE_FILTER)                  += vf_scale.o
 OBJS-$(CONFIG_SLICIFY_FILTER)                += vf_slicify.o

libavfilter/allfilters.c

@@ -39,6 +39,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER (FORMAT,      format,      vf);
     REGISTER_FILTER (NOFORMAT,    noformat,    vf);
     REGISTER_FILTER (NULL,        null,        vf);
+    REGISTER_FILTER (PAD,         pad,         vf);
     REGISTER_FILTER (PIXELASPECT, pixelaspect, vf);
     REGISTER_FILTER (SCALE,       scale,       vf);
     REGISTER_FILTER (SLICIFY,     slicify,     vf);

libavfilter/vf_pad.c

@@ -0,0 +1,326 @@
+/*
+ * copyright (c) 2008 vmrsss
+ * copyright (c) 2009 Stefano Sabatini
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file libavfilter/vf_pad.c
+ * video padding filter
+ */
+
+#include "avfilter.h"
+#include "parseutils.h"
+#include "libavutil/pixdesc.h"
+#include "libavcodec/colorspace.h"
+
+typedef struct {
+    int w, h;               ///< output dimensions, a value of 0 will result in the input size
+    int x, y;               ///< offsets of the input area with respect to the padded area
+    int in_w, in_h;         ///< width and height for the padded input video, which has to be aligned to the chroma values in order to avoid chroma issues
+
+    uint8_t color[4];       ///< color expressed either in YUVA or RGBA colorspace for the padding area
+    uint8_t *line[4];
+    int      line_step[4];
+    int hsub, vsub;         ///< chroma subsampling values
+} PadContext;
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+    PadContext *pad = ctx->priv;
+    char color_string[128] = "black";
+
+    if (args)
+        sscanf(args, "%d:%d:%d:%d:%s", &pad->w, &pad->h, &pad->x, &pad->y, color_string);
+
+    if (av_parse_color(pad->color, color_string, ctx) < 0)
+        return -1;
+
+    /* sanity check params */
+    if (pad->w < 0 || pad->h < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Negative size values are not acceptable.\n");
+        return -1;
+    }
+
+    return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    PadContext *pad = ctx->priv;
+    int i;
+
+    for (i = 0; i < 4; i++) {
+        av_freep(&pad->line[i]);
+        pad->line_step[i] = 0;
+    }
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum PixelFormat pix_fmts[] = {
+        PIX_FMT_ARGB,         PIX_FMT_RGBA,
+        PIX_FMT_ABGR,         PIX_FMT_BGRA,
+        PIX_FMT_RGB24,        PIX_FMT_BGR24,
+
+        PIX_FMT_YUV444P,      PIX_FMT_YUV422P,
+        PIX_FMT_YUV420P,      PIX_FMT_YUV411P,
+        PIX_FMT_YUV410P,      PIX_FMT_YUV440P,
+        PIX_FMT_YUVJ444P,     PIX_FMT_YUVJ422P,
+        PIX_FMT_YUVJ420P,     PIX_FMT_YUVJ440P,
+        PIX_FMT_YUVA420P,
+
+        PIX_FMT_NONE
+    };
+
+    avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
+    return 0;
+}
+
+enum { RED = 0, GREEN, BLUE, ALPHA };
+
+static int config_input(AVFilterLink *inlink)
+{
+    AVFilterContext *ctx = inlink->dst;
+    PadContext *pad = ctx->priv;
+    const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
+    uint8_t rgba_color[4];
+    uint8_t rgba_map[4];
+    int i, is_packed_rgb = 1;
+
+    switch (inlink->format) {
+    case PIX_FMT_ARGB:
+        rgba_map[ALPHA] = 0; rgba_map[RED] = 1; rgba_map[GREEN] = 2; rgba_map[BLUE] = 3;
+        break;
+    case PIX_FMT_ABGR:
+        rgba_map[ALPHA] = 0; rgba_map[BLUE] = 1; rgba_map[GREEN] = 2; rgba_map[RED] = 3;
+        break;
+    case PIX_FMT_RGBA:
+    case PIX_FMT_RGB24:
+        rgba_map[RED] = 0; rgba_map[GREEN] = 1; rgba_map[BLUE] = 2; rgba_map[ALPHA] = 3;
+        break;
+    case PIX_FMT_BGRA:
+    case PIX_FMT_BGR24:
+        rgba_map[BLUE] = 0; rgba_map[GREEN] = 1; rgba_map[RED] = 2; rgba_map[ALPHA] = 3;
+        break;
+    default:
+        is_packed_rgb = 0;
+    }
+
+    pad->hsub = pix_desc->log2_chroma_w;
+    pad->vsub = pix_desc->log2_chroma_h;
+
+    if (!pad->w)
+        pad->w = inlink->w;
+    if (!pad->h)
+        pad->h = inlink->h;
+
+    pad->w &= ~((1 << pad->hsub) - 1);
+    pad->h &= ~((1 << pad->vsub) - 1);
+    pad->x &= ~((1 << pad->hsub) - 1);
+    pad->y &= ~((1 << pad->vsub) - 1);
+
+    pad->in_w = inlink->w & ~((1 << pad->hsub) - 1);
+    pad->in_h = inlink->h & ~((1 << pad->vsub) - 1);
+
+    memcpy(rgba_color, pad->color, sizeof(rgba_color));
+    if (is_packed_rgb) {
+        pad->line_step[0] = (av_get_bits_per_pixel(&av_pix_fmt_descriptors[inlink->format]))>>3;
+        for (i = 0; i < 4; i++)
+            pad->color[rgba_map[i]] = rgba_color[i];
+
+        pad->line[0] = av_malloc(pad->w * pad->line_step[0]);
+        for (i = 0; i < pad->w; i++)
+            memcpy(pad->line[0] + i * pad->line_step[0], pad->color, pad->line_step[0]);
+    } else {
+        int plane;
+
+        pad->color[0] = RGB_TO_Y_CCIR(rgba_color[0], rgba_color[1], rgba_color[2]);
+        pad->color[1] = RGB_TO_U_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
+        pad->color[2] = RGB_TO_V_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
+        pad->color[3] = rgba_color[3];
+
+        for (plane = 0; plane < 4; plane++) {
+            int line_size;
+            int hsub = (plane == 1 || plane == 2) ? pad->hsub : 0;
+
+            pad->line_step[plane] = 1;
+            line_size = (pad->w >> hsub) * pad->line_step[plane];
+            pad->line[plane] = av_malloc(line_size);
+            memset(pad->line[plane], pad->color[plane], line_size);
+        }
+    }
+
+    av_log(ctx, AV_LOG_INFO, "w:%d h:%d x:%d y:%d color:0x%02X%02X%02X%02X[%s]\n",
+           pad->w, pad->h, pad->x, pad->y,
+           pad->color[0], pad->color[1], pad->color[2], pad->color[3],
+           is_packed_rgb ? "rgba" : "yuva");
+
+    if (pad->x <  0 || pad->y <  0                      ||
+        pad->w <= 0 || pad->h <= 0                      ||
+        (unsigned)pad->x + (unsigned)inlink->w > pad->w ||
+        (unsigned)pad->y + (unsigned)inlink->h > pad->h) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Input area %d:%d:%d:%d not within the padded area 0:0:%d:%d or zero-sized\n",
+               pad->x, pad->y, pad->x + inlink->w, pad->y + inlink->h, pad->w, pad->h);
+        return -1;
+    }
+
+    return 0;
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+    PadContext *pad = outlink->src->priv;
+
+    outlink->w = pad->w;
+    outlink->h = pad->h;
+    return 0;
+}
+
+static AVFilterPicRef *get_video_buffer(AVFilterLink *inlink, int perms, int w, int h)
+{
+    PadContext *pad = inlink->dst->priv;
+
+    AVFilterPicRef *picref = avfilter_get_video_buffer(inlink->dst->outputs[0], perms,
+                                                       w + (pad->w - pad->in_w),
+                                                       h + (pad->h - pad->in_h));
+
+    for (int plane = 0; plane < 4 && picref->data[plane]; plane++) {
+        int hsub = (plane == 1 || plane == 2) ? pad->hsub : 0;
+        int vsub = (plane == 1 || plane == 2) ? pad->vsub : 0;
+
+        picref->data[plane] += (pad->x >> hsub) * pad->line_step[plane] +
+            (pad->y >> vsub) * picref->linesize[plane];
+    }
+
+    return picref;
+}
+
+static void start_frame(AVFilterLink *inlink, AVFilterPicRef *inpicref)
+{
+    PadContext *pad = inlink->dst->priv;
+    AVFilterPicRef *outpicref = avfilter_ref_pic(inpicref, ~0);
+    inlink->dst->outputs[0]->outpic = outpicref;
+
+    for (int plane = 0; plane < 4 && outpicref->data[plane]; plane++) {
+        int hsub = (plane == 1 || plane == 2) ? pad->hsub : 0;
+        int vsub = (plane == 1 || plane == 2) ? pad->vsub : 0;
+
+        outpicref->data[plane] -= (pad->x >> hsub) * pad->line_step[plane] +
+            (pad->y >> vsub) * outpicref->linesize[plane];
+    }
+
+    avfilter_start_frame(inlink->dst->outputs[0], outpicref);
+}
+
+static void end_frame(AVFilterLink *link)
+{
+    avfilter_end_frame(link->dst->outputs[0]);
+    avfilter_unref_pic(link->cur_pic);
+}
+
+static void draw_rectangle(AVFilterPicRef *outpic, uint8_t *line[4], int line_step[4],
+                           int hsub, int vsub, int x, int y, int w, int h)
+{
+    int i, plane;
+    uint8_t *p;
+
+    for (plane = 0; plane < 4 && outpic->data[plane]; plane++) {
+        int hsub1 = plane == 1 || plane == 2 ? hsub : 0;
+        int vsub1 = plane == 1 || plane == 2 ? vsub : 0;
+
+        p = outpic->data[plane] + (y >> vsub1) * outpic->linesize[plane];
+        for (i = 0; i < (h >> vsub1); i++) {
+            memcpy(p + (x >> hsub1) * line_step[plane], line[plane], (w >> hsub1) * line_step[plane]);
+            p += outpic->linesize[plane];
+        }
+    }
+}
+
+static void draw_send_bar_slice(AVFilterLink *link, int y, int h, int slice_dir, int before_slice)
+{
+    PadContext *pad = link->dst->priv;
+    int bar_y, bar_h = 0;
+
+    if        (slice_dir * before_slice ==  1 && y == pad->y) {
+        /* top bar */
+        bar_y = 0;
+        bar_h = pad->y;
+    } else if (slice_dir * before_slice == -1 && (y + h) == (pad->y + pad->in_h)) {
+        /* bottom bar */
+        bar_y = pad->y + pad->in_h;
+        bar_h = pad->h - pad->in_h - pad->y;
+    }
+
+    if (bar_h) {
+        draw_rectangle(link->dst->outputs[0]->outpic,
+                       pad->line, pad->line_step, pad->hsub, pad->vsub,
+                       0, bar_y, pad->w, bar_h);
+        avfilter_draw_slice(link->dst->outputs[0], bar_y, bar_h, slice_dir);
+    }
+}
+
+static void draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
+{
+    PadContext *pad = link->dst->priv;
+    AVFilterPicRef *outpic = link->dst->outputs[0]->outpic;
+
+    y += pad->y;
+
+    y &= ~((1 << pad->vsub) - 1);
+    h &= ~((1 << pad->vsub) - 1);
+
+    if (!h)
+        return;
+    draw_send_bar_slice(link, y, h, slice_dir, 1);
+
+    /* left border */
+    draw_rectangle(outpic, pad->line, pad->line_step, pad->hsub, pad->vsub,
+                   0, y, pad->x, h);
+    /* right border */
+    draw_rectangle(outpic, pad->line, pad->line_step, pad->hsub, pad->vsub,
+                   pad->x + pad->in_w, y, pad->w - pad->x - pad->in_w, h);
+    avfilter_draw_slice(link->dst->outputs[0], y, h, slice_dir);
+
+    draw_send_bar_slice(link, y, h, slice_dir, -1);
+}
+
+AVFilter avfilter_vf_pad = {
+    .name          = "pad",
+    .description   = "Add pads to the input image.",
+
+    .priv_size     = sizeof(PadContext),
+    .init          = init,
+    .uninit        = uninit,
+    .query_formats = query_formats,
+
+    .inputs    = (AVFilterPad[]) {{ .name             = "default",
+                                    .type             = AVMEDIA_TYPE_VIDEO,
+                                    .config_props     = config_input,
+                                    .get_video_buffer = get_video_buffer,
+                                    .start_frame      = start_frame,
+                                    .draw_slice       = draw_slice,
+                                    .end_frame        = end_frame, },
+                                  { .name = NULL}},
+
+    .outputs   = (AVFilterPad[]) {{ .name             = "default",
+                                    .type             = AVMEDIA_TYPE_VIDEO,
+                                    .config_props     = config_output, },
+                                  { .name = NULL}},
+};