sierravmd.c 11 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332
  1. /*
  2. * Sierra VMD Format Demuxer
  3. * Copyright (c) 2004 The ffmpeg Project
  4. *
  5. * This file is part of FFmpeg.
  6. *
  7. * FFmpeg is free software; you can redistribute it and/or
  8. * modify it under the terms of the GNU Lesser General Public
  9. * License as published by the Free Software Foundation; either
  10. * version 2.1 of the License, or (at your option) any later version.
  11. *
  12. * FFmpeg is distributed in the hope that it will be useful,
  13. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15. * Lesser General Public License for more details.
  16. *
  17. * You should have received a copy of the GNU Lesser General Public
  18. * License along with FFmpeg; if not, write to the Free Software
  19. * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20. */
  21. /**
  22. * @file sierravmd.c
  23. * Sierra VMD file demuxer
  24. * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
  25. * for more information on the Sierra VMD file format, visit:
  26. * http://www.pcisys.net/~melanson/codecs/
  27. */
  28. #include "avformat.h"
  29. #define VMD_HEADER_SIZE 0x0330
  30. #define BYTES_PER_FRAME_RECORD 16
  31. typedef struct {
  32. int stream_index;
  33. offset_t frame_offset;
  34. unsigned int frame_size;
  35. int64_t pts;
  36. int keyframe;
  37. unsigned char frame_record[BYTES_PER_FRAME_RECORD];
  38. } vmd_frame_t;
  39. typedef struct VmdDemuxContext {
  40. int video_stream_index;
  41. int audio_stream_index;
  42. unsigned int audio_type;
  43. unsigned int audio_samplerate;
  44. unsigned int audio_bits;
  45. unsigned int audio_channels;
  46. unsigned int frame_count;
  47. unsigned int frames_per_block;
  48. vmd_frame_t *frame_table;
  49. unsigned int current_frame;
  50. int sample_rate;
  51. int64_t audio_sample_counter;
  52. int audio_frame_divisor;
  53. int audio_block_align;
  54. int skiphdr;
  55. unsigned char vmd_header[VMD_HEADER_SIZE];
  56. } VmdDemuxContext;
  57. static int vmd_probe(AVProbeData *p)
  58. {
  59. if (p->buf_size < 2)
  60. return 0;
  61. /* check if the first 2 bytes of the file contain the appropriate size
  62. * of a VMD header chunk */
  63. if (LE_16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
  64. return 0;
  65. /* only return half certainty since this check is a bit sketchy */
  66. return AVPROBE_SCORE_MAX / 2;
  67. }
  68. /* This is a support function to determine the duration, in sample
  69. * frames, of a particular audio chunk, taking into account silent
  70. * encodings. */
  71. static int vmd_calculate_audio_duration(unsigned char *audio_chunk,
  72. int audio_chunk_size, int block_align)
  73. {
  74. unsigned char *p = audio_chunk + 16;
  75. unsigned char *p_end = audio_chunk + audio_chunk_size;
  76. int total_samples = 0;
  77. unsigned int sound_flags;
  78. if (audio_chunk_size < 16)
  79. return 0;
  80. if (audio_chunk_size == block_align + 16)
  81. return block_align;
  82. if (audio_chunk_size == block_align + 17)
  83. return block_align;
  84. sound_flags = LE_32(p);
  85. p += 4;
  86. while (p < p_end) {
  87. total_samples += block_align;
  88. if ((sound_flags & 0x01) == 0)
  89. p += block_align;
  90. sound_flags >>= 1;
  91. }
  92. av_log(NULL,0,"Got %i samples for size %i map %08X\n", total_samples, audio_chunk_size, LE_32(audio_chunk));
  93. return total_samples;
  94. }
  95. static int vmd_read_header(AVFormatContext *s,
  96. AVFormatParameters *ap)
  97. {
  98. VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data;
  99. ByteIOContext *pb = &s->pb;
  100. AVStream *st;
  101. unsigned int toc_offset;
  102. unsigned char *raw_frame_table;
  103. int raw_frame_table_size;
  104. offset_t current_offset;
  105. int i, j;
  106. unsigned int total_frames;
  107. int64_t video_pts_inc = 0;
  108. int64_t current_video_pts = 0;
  109. unsigned char chunk[BYTES_PER_FRAME_RECORD];
  110. int lastframe = 0;
  111. /* fetch the main header, including the 2 header length bytes */
  112. url_fseek(pb, 0, SEEK_SET);
  113. if (get_buffer(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
  114. return AVERROR_IO;
  115. vmd->audio_sample_counter = 0;
  116. vmd->audio_frame_divisor = 1;
  117. vmd->audio_block_align = 1;
  118. /* start up the decoders */
  119. st = av_new_stream(s, 0);
  120. if (!st)
  121. return AVERROR_NOMEM;
  122. av_set_pts_info(st, 33, 1, 90000);
  123. vmd->video_stream_index = st->index;
  124. st->codec->codec_type = CODEC_TYPE_VIDEO;
  125. st->codec->codec_id = CODEC_ID_VMDVIDEO;
  126. st->codec->codec_tag = 0; /* no fourcc */
  127. st->codec->width = LE_16(&vmd->vmd_header[12]);
  128. st->codec->height = LE_16(&vmd->vmd_header[14]);
  129. st->codec->time_base.num = 1;
  130. st->codec->time_base.den = 10;
  131. st->codec->extradata_size = VMD_HEADER_SIZE;
  132. st->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
  133. memcpy(st->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
  134. /* if sample rate is 0, assume no audio */
  135. vmd->sample_rate = LE_16(&vmd->vmd_header[804]);
  136. if (vmd->sample_rate) {
  137. st = av_new_stream(s, 0);
  138. if (!st)
  139. return AVERROR_NOMEM;
  140. av_set_pts_info(st, 33, 1, 90000);
  141. vmd->audio_stream_index = st->index;
  142. st->codec->codec_type = CODEC_TYPE_AUDIO;
  143. st->codec->codec_id = CODEC_ID_VMDAUDIO;
  144. st->codec->codec_tag = 0; /* no fourcc */
  145. st->codec->channels = vmd->audio_channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
  146. st->codec->sample_rate = vmd->sample_rate;
  147. st->codec->block_align = vmd->audio_block_align =
  148. LE_16(&vmd->vmd_header[806]);
  149. if (st->codec->block_align & 0x8000) {
  150. st->codec->bits_per_sample = 16;
  151. st->codec->block_align = -(st->codec->block_align - 0x10000);
  152. vmd->audio_block_align = -(vmd->audio_block_align - 0x10000);
  153. } else {
  154. st->codec->bits_per_sample = 8;
  155. }
  156. st->codec->bit_rate = st->codec->sample_rate *
  157. st->codec->bits_per_sample * st->codec->channels;
  158. /* for calculating pts */
  159. vmd->audio_frame_divisor = st->codec->channels;
  160. video_pts_inc = 90000;
  161. video_pts_inc *= st->codec->block_align;
  162. video_pts_inc /= st->codec->sample_rate;
  163. video_pts_inc /= st->codec->channels;
  164. } else {
  165. /* if no audio, assume 10 frames/second */
  166. video_pts_inc = 90000 / 10;
  167. }
  168. toc_offset = LE_32(&vmd->vmd_header[812]);
  169. vmd->frame_count = LE_16(&vmd->vmd_header[6]);
  170. vmd->frames_per_block = LE_16(&vmd->vmd_header[18]);
  171. url_fseek(pb, toc_offset, SEEK_SET);
  172. raw_frame_table = NULL;
  173. vmd->frame_table = NULL;
  174. raw_frame_table_size = vmd->frame_count * 6;
  175. raw_frame_table = av_malloc(raw_frame_table_size);
  176. if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame_t)){
  177. av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
  178. return -1;
  179. }
  180. vmd->frame_table = av_malloc(vmd->frame_count * vmd->frames_per_block * sizeof(vmd_frame_t));
  181. if (!raw_frame_table || !vmd->frame_table) {
  182. av_free(raw_frame_table);
  183. av_free(vmd->frame_table);
  184. return AVERROR_NOMEM;
  185. }
  186. if (get_buffer(pb, raw_frame_table, raw_frame_table_size) !=
  187. raw_frame_table_size) {
  188. av_free(raw_frame_table);
  189. av_free(vmd->frame_table);
  190. return AVERROR_IO;
  191. }
  192. total_frames = 0;
  193. for (i = 0; i < vmd->frame_count; i++) {
  194. current_offset = LE_32(&raw_frame_table[6 * i + 2]);
  195. /* handle each entry in index block */
  196. for (j = 0; j < vmd->frames_per_block; j++) {
  197. int type;
  198. uint32_t size;
  199. get_buffer(pb, chunk, BYTES_PER_FRAME_RECORD);
  200. type = chunk[0];
  201. size = LE_32(&chunk[2]);
  202. if(!size)
  203. continue;
  204. switch(type) {
  205. case 1: /* Audio Chunk */
  206. vmd->frame_table[total_frames].frame_offset = current_offset;
  207. vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
  208. vmd->frame_table[total_frames].frame_size = size;
  209. memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
  210. total_frames++;
  211. break;
  212. case 2: /* Video Chunk */
  213. vmd->frame_table[total_frames].frame_offset = current_offset;
  214. vmd->frame_table[total_frames].frame_size = size;
  215. vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
  216. memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
  217. vmd->frame_table[total_frames].pts = current_video_pts;
  218. if (lastframe) {
  219. vmd->frame_table[lastframe].pts = current_video_pts - video_pts_inc;
  220. }
  221. lastframe = total_frames;
  222. total_frames++;
  223. break;
  224. }
  225. current_offset += size;
  226. }
  227. current_video_pts += video_pts_inc;
  228. }
  229. av_free(raw_frame_table);
  230. vmd->current_frame = 0;
  231. vmd->frame_count = total_frames;
  232. return 0;
  233. }
  234. static int vmd_read_packet(AVFormatContext *s,
  235. AVPacket *pkt)
  236. {
  237. VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data;
  238. ByteIOContext *pb = &s->pb;
  239. int ret = 0;
  240. vmd_frame_t *frame;
  241. if (vmd->current_frame >= vmd->frame_count)
  242. return AVERROR_IO;
  243. frame = &vmd->frame_table[vmd->current_frame];
  244. /* position the stream (will probably be there already) */
  245. url_fseek(pb, frame->frame_offset, SEEK_SET);
  246. if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))
  247. return AVERROR_NOMEM;
  248. pkt->pos= url_ftell(pb);
  249. memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
  250. ret = get_buffer(pb, pkt->data + BYTES_PER_FRAME_RECORD,
  251. frame->frame_size);
  252. if (ret != frame->frame_size) {
  253. av_free_packet(pkt);
  254. ret = AVERROR_IO;
  255. }
  256. pkt->stream_index = frame->stream_index;
  257. if (frame->frame_record[0] == 0x02)
  258. pkt->pts = frame->pts;
  259. else {
  260. pkt->pts = vmd->audio_sample_counter;
  261. pkt->pts *= 90000;
  262. pkt->pts /= vmd->sample_rate;
  263. pkt->pts /= vmd->audio_channels;
  264. vmd->audio_sample_counter += vmd_calculate_audio_duration(
  265. pkt->data, pkt->size, vmd->audio_block_align);
  266. }
  267. av_log(NULL, AV_LOG_INFO, " dispatching %s frame with %d bytes and pts %"PRId64" (%0.1f sec)\n",
  268. (frame->frame_record[0] == 0x02) ? "video" : "audio",
  269. frame->frame_size + BYTES_PER_FRAME_RECORD,
  270. pkt->pts, (float)(pkt->pts / 90000.0));
  271. vmd->current_frame++;
  272. return ret;
  273. }
  274. static int vmd_read_close(AVFormatContext *s)
  275. {
  276. VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data;
  277. av_free(vmd->frame_table);
  278. return 0;
  279. }
  280. AVInputFormat vmd_demuxer = {
  281. "vmd",
  282. "Sierra VMD format",
  283. sizeof(VmdDemuxContext),
  284. vmd_probe,
  285. vmd_read_header,
  286. vmd_read_packet,
  287. vmd_read_close,
  288. };