vp8_parser.c (2390B)
1 /* 2 * This file is part of FFmpeg. 3 * 4 * FFmpeg is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation; either 7 * version 2.1 of the License, or (at your option) any later version. 8 * 9 * FFmpeg is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Lesser General Public License for more details. 13 * 14 * You should have received a copy of the GNU Lesser General Public 15 * License along with FFmpeg; if not, write to the Free Software 16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 19 #include "libavutil/intreadwrite.h" 20 21 #include "avcodec.h" 22 23 static int parse(AVCodecParserContext *s, 24 AVCodecContext *avctx, 25 const uint8_t **poutbuf, int *poutbuf_size, 26 const uint8_t *buf, int buf_size) 27 { 28 unsigned int frame_type; 29 unsigned int profile; 30 31 *poutbuf = buf; 32 *poutbuf_size = buf_size; 33 34 if (buf_size < 3) 35 return buf_size; 36 37 frame_type = buf[0] & 1; 38 profile = (buf[0] >> 1) & 7; 39 if (profile > 3) { 40 av_log(avctx, AV_LOG_ERROR, "Invalid profile %u.\n", profile); 41 return buf_size; 42 } 43 44 avctx->profile = profile; 45 s->key_frame = frame_type == 0; 46 s->pict_type = frame_type ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I; 47 s->format = AV_PIX_FMT_YUV420P; 48 s->field_order = AV_FIELD_PROGRESSIVE; 49 s->picture_structure = AV_PICTURE_STRUCTURE_FRAME; 50 51 if (frame_type == 0) { 52 unsigned int sync_code; 53 unsigned int width, height; 54 55 if (buf_size < 10) 56 return buf_size; 57 58 sync_code = AV_RL24(buf + 3); 59 if (sync_code != 0x2a019d) { 60 av_log(avctx, AV_LOG_ERROR, "Invalid sync code %06x.\n", sync_code); 61 return buf_size; 62 } 63 64 width = AV_RL16(buf + 6) & 0x3fff; 65 height = AV_RL16(buf + 8) & 0x3fff; 66 67 s->width = width; 68 s->height = height; 69 s->coded_width = FFALIGN(width, 16); 70 s->coded_height = FFALIGN(height, 16); 71 } 72 73 return buf_size; 74 } 75 76 const AVCodecParser ff_vp8_parser = { 77 .codec_ids = { AV_CODEC_ID_VP8 }, 78 .parser_parse = parse, 79 };