| 1 | /* |
| 2 | * Microsoft XMV demuxer |
| 3 | * Copyright (c) 2011 Sven Hesse <drmccoy@drmccoy.de> |
| 4 | * Copyright (c) 2011 Matthew Hoops <clone2727@gmail.com> |
| 5 | * |
| 6 | * This file is part of FFmpeg. |
| 7 | * |
| 8 | * FFmpeg is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU Lesser General Public |
| 10 | * License as published by the Free Software Foundation; either |
| 11 | * version 2.1 of the License, or (at your option) any later version. |
| 12 | * |
| 13 | * FFmpeg is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * Lesser General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU Lesser General Public |
| 19 | * License along with FFmpeg; if not, write to the Free Software |
| 20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 21 | */ |
| 22 | |
| 23 | /** |
| 24 | * @file |
| 25 | * Microsoft XMV demuxer |
| 26 | */ |
| 27 | |
| 28 | #include <inttypes.h> |
| 29 | |
| 30 | #include "libavutil/intreadwrite.h" |
| 31 | |
| 32 | #include "avformat.h" |
| 33 | #include "internal.h" |
| 34 | #include "riff.h" |
| 35 | #include "libavutil/avassert.h" |
| 36 | |
| 37 | /** The min size of an XMV header. */ |
| 38 | #define XMV_MIN_HEADER_SIZE 36 |
| 39 | |
| 40 | /** Audio flag: ADPCM'd 5.1 stream, front left / right channels */ |
| 41 | #define XMV_AUDIO_ADPCM51_FRONTLEFTRIGHT 1 |
| 42 | /** Audio flag: ADPCM'd 5.1 stream, front center / low frequency channels */ |
| 43 | #define XMV_AUDIO_ADPCM51_FRONTCENTERLOW 2 |
| 44 | /** Audio flag: ADPCM'd 5.1 stream, rear left / right channels */ |
| 45 | #define XMV_AUDIO_ADPCM51_REARLEFTRIGHT 4 |
| 46 | |
| 47 | /** Audio flag: Any of the ADPCM'd 5.1 stream flags. */ |
| 48 | #define XMV_AUDIO_ADPCM51 (XMV_AUDIO_ADPCM51_FRONTLEFTRIGHT | \ |
| 49 | XMV_AUDIO_ADPCM51_FRONTCENTERLOW | \ |
| 50 | XMV_AUDIO_ADPCM51_REARLEFTRIGHT) |
| 51 | |
| 52 | #define XMV_BLOCK_ALIGN_SIZE 36 |
| 53 | |
| 54 | /** A video packet with an XMV file. */ |
| 55 | typedef struct XMVVideoPacket { |
| 56 | int stream_index; ///< The decoder stream index for this video packet. |
| 57 | |
| 58 | uint32_t data_size; ///< The size of the remaining video data. |
| 59 | uint64_t data_offset; ///< The offset of the video data within the file. |
| 60 | |
| 61 | uint32_t current_frame; ///< The current frame within this video packet. |
| 62 | uint32_t frame_count; ///< The amount of frames within this video packet. |
| 63 | |
| 64 | int has_extradata; ///< Does the video packet contain extra data? |
| 65 | uint8_t extradata[4]; ///< The extra data |
| 66 | |
| 67 | int64_t last_pts; ///< PTS of the last video frame. |
| 68 | int64_t pts; ///< PTS of the most current video frame. |
| 69 | } XMVVideoPacket; |
| 70 | |
| 71 | /** An audio packet with an XMV file. */ |
| 72 | typedef struct XMVAudioPacket { |
| 73 | int stream_index; ///< The decoder stream index for this audio packet. |
| 74 | |
| 75 | /* Stream format properties. */ |
| 76 | uint16_t compression; ///< The type of compression. |
| 77 | uint16_t channels; ///< Number of channels. |
| 78 | uint32_t sample_rate; ///< Sampling rate. |
| 79 | uint16_t bits_per_sample; ///< Bits per compressed sample. |
| 80 | uint32_t bit_rate; ///< Bits of compressed data per second. |
| 81 | uint16_t flags; ///< Flags |
| 82 | unsigned block_align; ///< Bytes per compressed block. |
| 83 | uint16_t block_samples; ///< Decompressed samples per compressed block. |
| 84 | |
| 85 | enum AVCodecID codec_id; ///< The codec ID of the compression scheme. |
| 86 | |
| 87 | uint32_t data_size; ///< The size of the remaining audio data. |
| 88 | uint64_t data_offset; ///< The offset of the audio data within the file. |
| 89 | |
| 90 | uint32_t frame_size; ///< Number of bytes to put into an audio frame. |
| 91 | |
| 92 | uint64_t block_count; ///< Running counter of decompressed audio block. |
| 93 | } XMVAudioPacket; |
| 94 | |
| 95 | /** Context for demuxing an XMV file. */ |
| 96 | typedef struct XMVDemuxContext { |
| 97 | uint16_t audio_track_count; ///< Number of audio track in this file. |
| 98 | |
| 99 | uint32_t this_packet_size; ///< Size of the current packet. |
| 100 | uint32_t next_packet_size; ///< Size of the next packet. |
| 101 | |
| 102 | uint64_t this_packet_offset; ///< Offset of the current packet. |
| 103 | uint64_t next_packet_offset; ///< Offset of the next packet. |
| 104 | |
| 105 | uint16_t current_stream; ///< The index of the stream currently handling. |
| 106 | uint16_t stream_count; ///< The number of streams in this file. |
| 107 | |
| 108 | XMVVideoPacket video; ///< The video packet contained in each packet. |
| 109 | XMVAudioPacket *audio; ///< The audio packets contained in each packet. |
| 110 | } XMVDemuxContext; |
| 111 | |
| 112 | static int xmv_probe(AVProbeData *p) |
| 113 | { |
| 114 | uint32_t file_version; |
| 115 | |
| 116 | if (p->buf_size < XMV_MIN_HEADER_SIZE) |
| 117 | return 0; |
| 118 | |
| 119 | file_version = AV_RL32(p->buf + 16); |
| 120 | if ((file_version == 0) || (file_version > 4)) |
| 121 | return 0; |
| 122 | |
| 123 | if (!memcmp(p->buf + 12, "xobX", 4)) |
| 124 | return AVPROBE_SCORE_MAX; |
| 125 | |
| 126 | return 0; |
| 127 | } |
| 128 | |
| 129 | static int xmv_read_close(AVFormatContext *s) |
| 130 | { |
| 131 | XMVDemuxContext *xmv = s->priv_data; |
| 132 | |
| 133 | av_freep(&xmv->audio); |
| 134 | |
| 135 | return 0; |
| 136 | } |
| 137 | |
| 138 | static int xmv_read_header(AVFormatContext *s) |
| 139 | { |
| 140 | XMVDemuxContext *xmv = s->priv_data; |
| 141 | AVIOContext *pb = s->pb; |
| 142 | AVStream *vst = NULL; |
| 143 | |
| 144 | uint32_t file_version; |
| 145 | uint32_t this_packet_size; |
| 146 | uint16_t audio_track; |
| 147 | int ret; |
| 148 | |
| 149 | avio_skip(pb, 4); /* Next packet size */ |
| 150 | |
| 151 | this_packet_size = avio_rl32(pb); |
| 152 | |
| 153 | avio_skip(pb, 4); /* Max packet size */ |
| 154 | avio_skip(pb, 4); /* "xobX" */ |
| 155 | |
| 156 | file_version = avio_rl32(pb); |
| 157 | if ((file_version != 4) && (file_version != 2)) |
| 158 | avpriv_request_sample(s, "Uncommon version %"PRIu32"", file_version); |
| 159 | |
| 160 | |
| 161 | /* Video track */ |
| 162 | |
| 163 | vst = avformat_new_stream(s, NULL); |
| 164 | if (!vst) |
| 165 | return AVERROR(ENOMEM); |
| 166 | |
| 167 | avpriv_set_pts_info(vst, 32, 1, 1000); |
| 168 | |
| 169 | vst->codec->codec_type = AVMEDIA_TYPE_VIDEO; |
| 170 | vst->codec->codec_id = AV_CODEC_ID_WMV2; |
| 171 | vst->codec->codec_tag = MKBETAG('W', 'M', 'V', '2'); |
| 172 | vst->codec->width = avio_rl32(pb); |
| 173 | vst->codec->height = avio_rl32(pb); |
| 174 | |
| 175 | vst->duration = avio_rl32(pb); |
| 176 | |
| 177 | xmv->video.stream_index = vst->index; |
| 178 | |
| 179 | /* Audio tracks */ |
| 180 | |
| 181 | xmv->audio_track_count = avio_rl16(pb); |
| 182 | |
| 183 | avio_skip(pb, 2); /* Unknown (padding?) */ |
| 184 | |
| 185 | xmv->audio = av_malloc_array(xmv->audio_track_count, sizeof(XMVAudioPacket)); |
| 186 | if (!xmv->audio) { |
| 187 | ret = AVERROR(ENOMEM); |
| 188 | goto fail; |
| 189 | } |
| 190 | |
| 191 | for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) { |
| 192 | XMVAudioPacket *packet = &xmv->audio[audio_track]; |
| 193 | AVStream *ast = NULL; |
| 194 | |
| 195 | packet->compression = avio_rl16(pb); |
| 196 | packet->channels = avio_rl16(pb); |
| 197 | packet->sample_rate = avio_rl32(pb); |
| 198 | packet->bits_per_sample = avio_rl16(pb); |
| 199 | packet->flags = avio_rl16(pb); |
| 200 | |
| 201 | packet->bit_rate = packet->bits_per_sample * |
| 202 | packet->sample_rate * |
| 203 | packet->channels; |
| 204 | packet->block_align = XMV_BLOCK_ALIGN_SIZE * packet->channels; |
| 205 | packet->block_samples = 64; |
| 206 | packet->codec_id = ff_wav_codec_get_id(packet->compression, |
| 207 | packet->bits_per_sample); |
| 208 | |
| 209 | packet->stream_index = -1; |
| 210 | |
| 211 | packet->frame_size = 0; |
| 212 | packet->block_count = 0; |
| 213 | |
| 214 | /* TODO: ADPCM'd 5.1 sound is encoded in three separate streams. |
| 215 | * Those need to be interleaved to a proper 5.1 stream. */ |
| 216 | if (packet->flags & XMV_AUDIO_ADPCM51) |
| 217 | av_log(s, AV_LOG_WARNING, "Unsupported 5.1 ADPCM audio stream " |
| 218 | "(0x%04X)\n", packet->flags); |
| 219 | |
| 220 | if (!packet->channels || !packet->sample_rate || |
| 221 | packet->channels >= UINT16_MAX / XMV_BLOCK_ALIGN_SIZE) { |
| 222 | av_log(s, AV_LOG_ERROR, "Invalid parameters for audio track %"PRIu16".\n", |
| 223 | audio_track); |
| 224 | ret = AVERROR_INVALIDDATA; |
| 225 | goto fail; |
| 226 | } |
| 227 | |
| 228 | ast = avformat_new_stream(s, NULL); |
| 229 | if (!ast) { |
| 230 | ret = AVERROR(ENOMEM); |
| 231 | goto fail; |
| 232 | } |
| 233 | |
| 234 | ast->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 235 | ast->codec->codec_id = packet->codec_id; |
| 236 | ast->codec->codec_tag = packet->compression; |
| 237 | ast->codec->channels = packet->channels; |
| 238 | ast->codec->sample_rate = packet->sample_rate; |
| 239 | ast->codec->bits_per_coded_sample = packet->bits_per_sample; |
| 240 | ast->codec->bit_rate = packet->bit_rate; |
| 241 | ast->codec->block_align = 36 * packet->channels; |
| 242 | |
| 243 | avpriv_set_pts_info(ast, 32, packet->block_samples, packet->sample_rate); |
| 244 | |
| 245 | packet->stream_index = ast->index; |
| 246 | |
| 247 | ast->duration = vst->duration; |
| 248 | } |
| 249 | |
| 250 | |
| 251 | /* Initialize the packet context */ |
| 252 | |
| 253 | xmv->next_packet_offset = avio_tell(pb); |
| 254 | xmv->next_packet_size = this_packet_size - xmv->next_packet_offset; |
| 255 | xmv->stream_count = xmv->audio_track_count + 1; |
| 256 | |
| 257 | return 0; |
| 258 | |
| 259 | fail: |
| 260 | xmv_read_close(s); |
| 261 | return ret; |
| 262 | } |
| 263 | |
| 264 | static void xmv_read_extradata(uint8_t *extradata, AVIOContext *pb) |
| 265 | { |
| 266 | /* Read the XMV extradata */ |
| 267 | |
| 268 | uint32_t data = avio_rl32(pb); |
| 269 | |
| 270 | int mspel_bit = !!(data & 0x01); |
| 271 | int loop_filter = !!(data & 0x02); |
| 272 | int abt_flag = !!(data & 0x04); |
| 273 | int j_type_bit = !!(data & 0x08); |
| 274 | int top_left_mv_flag = !!(data & 0x10); |
| 275 | int per_mb_rl_bit = !!(data & 0x20); |
| 276 | int slice_count = (data >> 6) & 7; |
| 277 | |
| 278 | /* Write it back as standard WMV2 extradata */ |
| 279 | |
| 280 | data = 0; |
| 281 | |
| 282 | data |= mspel_bit << 15; |
| 283 | data |= loop_filter << 14; |
| 284 | data |= abt_flag << 13; |
| 285 | data |= j_type_bit << 12; |
| 286 | data |= top_left_mv_flag << 11; |
| 287 | data |= per_mb_rl_bit << 10; |
| 288 | data |= slice_count << 7; |
| 289 | |
| 290 | AV_WB32(extradata, data); |
| 291 | } |
| 292 | |
| 293 | static int xmv_process_packet_header(AVFormatContext *s) |
| 294 | { |
| 295 | XMVDemuxContext *xmv = s->priv_data; |
| 296 | AVIOContext *pb = s->pb; |
| 297 | |
| 298 | uint8_t data[8]; |
| 299 | uint16_t audio_track; |
| 300 | uint64_t data_offset; |
| 301 | |
| 302 | /* Next packet size */ |
| 303 | xmv->next_packet_size = avio_rl32(pb); |
| 304 | |
| 305 | /* Packet video header */ |
| 306 | |
| 307 | if (avio_read(pb, data, 8) != 8) |
| 308 | return AVERROR(EIO); |
| 309 | |
| 310 | xmv->video.data_size = AV_RL32(data) & 0x007FFFFF; |
| 311 | |
| 312 | xmv->video.current_frame = 0; |
| 313 | xmv->video.frame_count = (AV_RL32(data) >> 23) & 0xFF; |
| 314 | |
| 315 | xmv->video.has_extradata = (data[3] & 0x80) != 0; |
| 316 | |
| 317 | /* Adding the audio data sizes and the video data size keeps you 4 bytes |
| 318 | * short for every audio track. But as playing around with XMV files with |
| 319 | * ADPCM audio showed, taking the extra 4 bytes from the audio data gives |
| 320 | * you either completely distorted audio or click (when skipping the |
| 321 | * remaining 68 bytes of the ADPCM block). Subtracting 4 bytes for every |
| 322 | * audio track from the video data works at least for the audio. Probably |
| 323 | * some alignment thing? |
| 324 | * The video data has (always?) lots of padding, so it should work out... |
| 325 | */ |
| 326 | xmv->video.data_size -= xmv->audio_track_count * 4; |
| 327 | |
| 328 | xmv->current_stream = 0; |
| 329 | if (!xmv->video.frame_count) { |
| 330 | xmv->video.frame_count = 1; |
| 331 | xmv->current_stream = xmv->stream_count > 1; |
| 332 | } |
| 333 | |
| 334 | /* Packet audio header */ |
| 335 | |
| 336 | for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) { |
| 337 | XMVAudioPacket *packet = &xmv->audio[audio_track]; |
| 338 | |
| 339 | if (avio_read(pb, data, 4) != 4) |
| 340 | return AVERROR(EIO); |
| 341 | |
| 342 | packet->data_size = AV_RL32(data) & 0x007FFFFF; |
| 343 | if ((packet->data_size == 0) && (audio_track != 0)) |
| 344 | /* This happens when I create an XMV with several identical audio |
| 345 | * streams. From the size calculations, duplicating the previous |
| 346 | * stream's size works out, but the track data itself is silent. |
| 347 | * Maybe this should also redirect the offset to the previous track? |
| 348 | */ |
| 349 | packet->data_size = xmv->audio[audio_track - 1].data_size; |
| 350 | |
| 351 | /* Carve up the audio data in frame_count slices */ |
| 352 | packet->frame_size = packet->data_size / xmv->video.frame_count; |
| 353 | packet->frame_size -= packet->frame_size % packet->block_align; |
| 354 | } |
| 355 | |
| 356 | /* Packet data offsets */ |
| 357 | |
| 358 | data_offset = avio_tell(pb); |
| 359 | |
| 360 | xmv->video.data_offset = data_offset; |
| 361 | data_offset += xmv->video.data_size; |
| 362 | |
| 363 | for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) { |
| 364 | xmv->audio[audio_track].data_offset = data_offset; |
| 365 | data_offset += xmv->audio[audio_track].data_size; |
| 366 | } |
| 367 | |
| 368 | /* Video frames header */ |
| 369 | |
| 370 | /* Read new video extra data */ |
| 371 | if (xmv->video.data_size > 0) { |
| 372 | if (xmv->video.has_extradata) { |
| 373 | xmv_read_extradata(xmv->video.extradata, pb); |
| 374 | |
| 375 | xmv->video.data_size -= 4; |
| 376 | xmv->video.data_offset += 4; |
| 377 | |
| 378 | if (xmv->video.stream_index >= 0) { |
| 379 | AVStream *vst = s->streams[xmv->video.stream_index]; |
| 380 | |
| 381 | av_assert0(xmv->video.stream_index < s->nb_streams); |
| 382 | |
| 383 | if (vst->codec->extradata_size < 4) { |
| 384 | av_free(vst->codec->extradata); |
| 385 | |
| 386 | ff_alloc_extradata(vst->codec, 4); |
| 387 | } |
| 388 | |
| 389 | memcpy(vst->codec->extradata, xmv->video.extradata, 4); |
| 390 | } |
| 391 | } |
| 392 | } |
| 393 | |
| 394 | return 0; |
| 395 | } |
| 396 | |
| 397 | static int xmv_fetch_new_packet(AVFormatContext *s) |
| 398 | { |
| 399 | XMVDemuxContext *xmv = s->priv_data; |
| 400 | AVIOContext *pb = s->pb; |
| 401 | int result; |
| 402 | |
| 403 | if (xmv->this_packet_offset == xmv->next_packet_offset) |
| 404 | return AVERROR_EOF; |
| 405 | |
| 406 | /* Seek to it */ |
| 407 | xmv->this_packet_offset = xmv->next_packet_offset; |
| 408 | if (avio_seek(pb, xmv->this_packet_offset, SEEK_SET) != xmv->this_packet_offset) |
| 409 | return AVERROR(EIO); |
| 410 | |
| 411 | /* Update the size */ |
| 412 | xmv->this_packet_size = xmv->next_packet_size; |
| 413 | if (xmv->this_packet_size < (12 + xmv->audio_track_count * 4)) |
| 414 | return AVERROR(EIO); |
| 415 | |
| 416 | /* Process the header */ |
| 417 | result = xmv_process_packet_header(s); |
| 418 | if (result) |
| 419 | return result; |
| 420 | |
| 421 | /* Update the offset */ |
| 422 | xmv->next_packet_offset = xmv->this_packet_offset + xmv->this_packet_size; |
| 423 | |
| 424 | return 0; |
| 425 | } |
| 426 | |
| 427 | static int xmv_fetch_audio_packet(AVFormatContext *s, |
| 428 | AVPacket *pkt, uint32_t stream) |
| 429 | { |
| 430 | XMVDemuxContext *xmv = s->priv_data; |
| 431 | AVIOContext *pb = s->pb; |
| 432 | XMVAudioPacket *audio = &xmv->audio[stream]; |
| 433 | |
| 434 | uint32_t data_size; |
| 435 | uint32_t block_count; |
| 436 | int result; |
| 437 | |
| 438 | /* Seek to it */ |
| 439 | if (avio_seek(pb, audio->data_offset, SEEK_SET) != audio->data_offset) |
| 440 | return AVERROR(EIO); |
| 441 | |
| 442 | if ((xmv->video.current_frame + 1) < xmv->video.frame_count) |
| 443 | /* Not the last frame, get at most frame_size bytes. */ |
| 444 | data_size = FFMIN(audio->frame_size, audio->data_size); |
| 445 | else |
| 446 | /* Last frame, get the rest. */ |
| 447 | data_size = audio->data_size; |
| 448 | |
| 449 | /* Read the packet */ |
| 450 | result = av_get_packet(pb, pkt, data_size); |
| 451 | if (result <= 0) |
| 452 | return result; |
| 453 | |
| 454 | pkt->stream_index = audio->stream_index; |
| 455 | |
| 456 | /* Calculate the PTS */ |
| 457 | |
| 458 | block_count = data_size / audio->block_align; |
| 459 | |
| 460 | pkt->duration = block_count; |
| 461 | pkt->pts = audio->block_count; |
| 462 | pkt->dts = AV_NOPTS_VALUE; |
| 463 | |
| 464 | audio->block_count += block_count; |
| 465 | |
| 466 | /* Advance offset */ |
| 467 | audio->data_size -= data_size; |
| 468 | audio->data_offset += data_size; |
| 469 | |
| 470 | return 0; |
| 471 | } |
| 472 | |
| 473 | static int xmv_fetch_video_packet(AVFormatContext *s, |
| 474 | AVPacket *pkt) |
| 475 | { |
| 476 | XMVDemuxContext *xmv = s->priv_data; |
| 477 | AVIOContext *pb = s->pb; |
| 478 | XMVVideoPacket *video = &xmv->video; |
| 479 | |
| 480 | int result; |
| 481 | uint32_t frame_header; |
| 482 | uint32_t frame_size, frame_timestamp; |
| 483 | uint8_t *data, *end; |
| 484 | |
| 485 | /* Seek to it */ |
| 486 | if (avio_seek(pb, video->data_offset, SEEK_SET) != video->data_offset) |
| 487 | return AVERROR(EIO); |
| 488 | |
| 489 | /* Read the frame header */ |
| 490 | frame_header = avio_rl32(pb); |
| 491 | |
| 492 | frame_size = (frame_header & 0x1FFFF) * 4 + 4; |
| 493 | frame_timestamp = (frame_header >> 17); |
| 494 | |
| 495 | if ((frame_size + 4) > video->data_size) |
| 496 | return AVERROR(EIO); |
| 497 | |
| 498 | /* Get the packet data */ |
| 499 | result = av_get_packet(pb, pkt, frame_size); |
| 500 | if (result != frame_size) |
| 501 | return result; |
| 502 | |
| 503 | /* Contrary to normal WMV2 video, the bit stream in XMV's |
| 504 | * WMV2 is little-endian. |
| 505 | * TODO: This manual swap is of course suboptimal. |
| 506 | */ |
| 507 | for (data = pkt->data, end = pkt->data + frame_size; data < end; data += 4) |
| 508 | AV_WB32(data, AV_RL32(data)); |
| 509 | |
| 510 | pkt->stream_index = video->stream_index; |
| 511 | |
| 512 | /* Calculate the PTS */ |
| 513 | |
| 514 | video->last_pts = frame_timestamp + video->pts; |
| 515 | |
| 516 | pkt->duration = 0; |
| 517 | pkt->pts = video->last_pts; |
| 518 | pkt->dts = AV_NOPTS_VALUE; |
| 519 | |
| 520 | video->pts += frame_timestamp; |
| 521 | |
| 522 | /* Keyframe? */ |
| 523 | pkt->flags = (pkt->data[0] & 0x80) ? 0 : AV_PKT_FLAG_KEY; |
| 524 | |
| 525 | /* Advance offset */ |
| 526 | video->data_size -= frame_size + 4; |
| 527 | video->data_offset += frame_size + 4; |
| 528 | |
| 529 | return 0; |
| 530 | } |
| 531 | |
| 532 | static int xmv_read_packet(AVFormatContext *s, |
| 533 | AVPacket *pkt) |
| 534 | { |
| 535 | XMVDemuxContext *xmv = s->priv_data; |
| 536 | int result; |
| 537 | |
| 538 | if (xmv->video.current_frame == xmv->video.frame_count) { |
| 539 | /* No frames left in this packet, so we fetch a new one */ |
| 540 | |
| 541 | result = xmv_fetch_new_packet(s); |
| 542 | if (result) |
| 543 | return result; |
| 544 | } |
| 545 | |
| 546 | if (xmv->current_stream == 0) { |
| 547 | /* Fetch a video frame */ |
| 548 | |
| 549 | result = xmv_fetch_video_packet(s, pkt); |
| 550 | if (result) |
| 551 | return result; |
| 552 | |
| 553 | } else { |
| 554 | /* Fetch an audio frame */ |
| 555 | |
| 556 | result = xmv_fetch_audio_packet(s, pkt, xmv->current_stream - 1); |
| 557 | if (result) |
| 558 | return result; |
| 559 | } |
| 560 | |
| 561 | /* Increase our counters */ |
| 562 | if (++xmv->current_stream >= xmv->stream_count) { |
| 563 | xmv->current_stream = 0; |
| 564 | xmv->video.current_frame += 1; |
| 565 | } |
| 566 | |
| 567 | return 0; |
| 568 | } |
| 569 | |
| 570 | AVInputFormat ff_xmv_demuxer = { |
| 571 | .name = "xmv", |
| 572 | .long_name = NULL_IF_CONFIG_SMALL("Microsoft XMV"), |
| 573 | .priv_data_size = sizeof(XMVDemuxContext), |
| 574 | .read_probe = xmv_probe, |
| 575 | .read_header = xmv_read_header, |
| 576 | .read_packet = xmv_read_packet, |
| 577 | .read_close = xmv_read_close, |
| 578 | }; |