119 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			119 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * Copyright (C) 2008 Michael Niedermayer
 | |
|  *
 | |
|  * 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
 | |
|  */
 | |
| 
 | |
| #include "libavutil/intreadwrite.h"
 | |
| #include "parser.h"
 | |
| 
 | |
| typedef struct VP9ParseContext {
 | |
|     int n_frames; // 1-8
 | |
|     int size[8];
 | |
| } VP9ParseContext;
 | |
| 
 | |
| static void parse_frame(AVCodecParserContext *ctx, const uint8_t *buf, int size)
 | |
| {
 | |
|     if (buf[0] & 0x4) {
 | |
|         ctx->pict_type = AV_PICTURE_TYPE_P;
 | |
|         ctx->key_frame = 0;
 | |
|     } else {
 | |
|         ctx->pict_type = AV_PICTURE_TYPE_I;
 | |
|         ctx->key_frame = 1;
 | |
|     }
 | |
| }
 | |
| 
 | |
| static int parse(AVCodecParserContext *ctx,
 | |
|                  AVCodecContext *avctx,
 | |
|                  const uint8_t **out_data, int *out_size,
 | |
|                  const uint8_t *data, int size)
 | |
| {
 | |
|     VP9ParseContext *s = ctx->priv_data;
 | |
|     int marker;
 | |
| 
 | |
|     if (size <= 0) {
 | |
|         *out_size = 0;
 | |
|         *out_data = data;
 | |
| 
 | |
|         return 0;
 | |
|     }
 | |
| 
 | |
|     if (s->n_frames > 0) {
 | |
|         *out_data = data;
 | |
|         *out_size = s->size[--s->n_frames];
 | |
|         parse_frame(ctx, *out_data, *out_size);
 | |
| 
 | |
|         return s->n_frames > 0 ? *out_size : size /* i.e. include idx tail */;
 | |
|     }
 | |
| 
 | |
|     marker = data[size - 1];
 | |
|     if ((marker & 0xe0) == 0xc0) {
 | |
|         int nbytes = 1 + ((marker >> 3) & 0x3);
 | |
|         int n_frames = 1 + (marker & 0x7), idx_sz = 2 + n_frames * nbytes;
 | |
| 
 | |
|         if (size >= idx_sz && data[size - idx_sz] == marker) {
 | |
|             const uint8_t *idx = data + size + 1 - idx_sz;
 | |
|             int first = 1;
 | |
| 
 | |
|             switch (nbytes) {
 | |
| #define case_n(a, rd) \
 | |
|             case a: \
 | |
|                 while (n_frames--) { \
 | |
|                     unsigned sz = rd; \
 | |
|                     idx += a; \
 | |
|                     if (sz > size) { \
 | |
|                         s->n_frames = 0; \
 | |
|                         av_log(avctx, AV_LOG_ERROR, \
 | |
|                                "Superframe packet size too big: %u > %d\n", \
 | |
|                                sz, size); \
 | |
|                         return size; \
 | |
|                     } \
 | |
|                     if (first) { \
 | |
|                         first = 0; \
 | |
|                         *out_data = data; \
 | |
|                         *out_size = sz; \
 | |
|                         s->n_frames = n_frames; \
 | |
|                     } else { \
 | |
|                         s->size[n_frames] = sz; \
 | |
|                     } \
 | |
|                     data += sz; \
 | |
|                     size -= sz; \
 | |
|                 } \
 | |
|                 parse_frame(ctx, *out_data, *out_size); \
 | |
|                 return *out_size
 | |
| 
 | |
|                 case_n(1, *idx);
 | |
|                 case_n(2, AV_RL16(idx));
 | |
|                 case_n(3, AV_RL24(idx));
 | |
|                 case_n(4, AV_RL32(idx));
 | |
|             }
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     *out_data = data;
 | |
|     *out_size = size;
 | |
|     parse_frame(ctx, data, size);
 | |
| 
 | |
|     return size;
 | |
| }
 | |
| 
 | |
| AVCodecParser ff_vp9_parser = {
 | |
|     .codec_ids      = { AV_CODEC_ID_VP9 },
 | |
|     .priv_data_size = sizeof(VP9ParseContext),
 | |
|     .parser_parse   = parse,
 | |
| };
 |