FFmpeg  4.3.9
tak_parser.c
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1 /*
2  * TAK parser
3  * Copyright (c) 2012 Michael Niedermayer
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 /**
23  * @file
24  * TAK parser
25  **/
26 
27 #define BITSTREAM_READER_LE
28 #include "parser.h"
29 #include "tak.h"
30 
31 typedef struct TAKParseContext {
34  int index;
36 
38  const uint8_t **poutbuf, int *poutbuf_size,
39  const uint8_t *buf, int buf_size)
40 {
41  TAKParseContext *t = s->priv_data;
42  ParseContext *pc = &t->pc;
43  int next = END_NOT_FOUND;
44  GetBitContext gb;
45  int consumed = 0;
46  int needed = buf_size ? TAK_MAX_FRAME_HEADER_BYTES : 8;
47  int ret;
48 
49  *poutbuf = buf;
50  *poutbuf_size = buf_size;
51 
54  if ((ret = init_get_bits8(&gb, buf, buf_size)) < 0)
55  return buf_size;
56  if (!ff_tak_decode_frame_header(avctx, &gb, &ti, 127))
58  : t->ti.frame_samples;
59  return buf_size;
60  }
61 
62  while (buf_size || t->index + needed <= pc->index) {
63  if (buf_size && t->index + TAK_MAX_FRAME_HEADER_BYTES > pc->index) {
64  int tmp_buf_size = FFMIN(TAK_MAX_FRAME_HEADER_BYTES,
65  buf_size);
66  const uint8_t *tmp_buf = buf;
67 
68  if (ff_combine_frame(pc, END_NOT_FOUND, &tmp_buf, &tmp_buf_size) != -1)
69  goto fail;
70  consumed += tmp_buf_size;
71  buf += tmp_buf_size;
72  buf_size -= tmp_buf_size;
73  }
74 
75  for (; t->index + needed <= pc->index; t->index++) {
76  if (pc->buffer[ t->index ] == 0xFF &&
77  pc->buffer[ t->index + 1 ] == 0xA0) {
79 
80  if ((ret = init_get_bits8(&gb, pc->buffer + t->index,
81  pc->index - t->index)) < 0)
82  goto fail;
83  if (!ff_tak_decode_frame_header(avctx, &gb,
84  pc->frame_start_found ? &ti : &t->ti, 127) &&
85  !ff_tak_check_crc(pc->buffer + t->index,
86  get_bits_count(&gb) / 8)) {
87  if (!pc->frame_start_found) {
88  pc->frame_start_found = 1;
91  t->ti.frame_samples;
93  } else {
94  pc->frame_start_found = 0;
95  next = t->index - pc->index;
96  t->index = 0;
97  goto found;
98  }
99  }
100  }
101  }
102  }
103 found:
104 
105  if (consumed && !buf_size && next == END_NOT_FOUND ||
106  ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
107  goto fail;
108  }
109 
110  if (next != END_NOT_FOUND) {
111  next += consumed;
112  pc->overread = FFMAX(0, -next);
113  }
114 
115  *poutbuf = buf;
116  *poutbuf_size = buf_size;
117  return next;
118 
119 fail:
120  *poutbuf = NULL;
121  *poutbuf_size = 0;
122  return buf_size + consumed;
123 }
124 
126  .codec_ids = { AV_CODEC_ID_TAK },
127  .priv_data_size = sizeof(TAKParseContext),
128  .parser_parse = tak_parse,
129  .parser_close = ff_parse_close,
130 };
#define NULL
Definition: coverity.c:32
int ff_tak_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb, TAKStreamInfo *ti, int log_level_offset)
Validate and decode a frame header.
Definition: tak.c:141
int codec_ids[5]
Definition: avcodec.h:3525
AVCodecParser ff_tak_parser
Definition: tak_parser.c:125
int duration
Duration of the current frame.
Definition: avcodec.h:3479
int frame_start_found
Definition: parser.h:34
TAKStreamInfo ti
Definition: tak_parser.c:33
uint8_t
int flags
Definition: tak.h:129
static int tak_parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition: tak_parser.c:37
int ff_tak_check_crc(const uint8_t *buf, unsigned int buf_size)
Definition: tak.c:77
#define TAK_FRAME_FLAG_HAS_INFO
Definition: tak.h:61
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:219
int ff_combine_frame(ParseContext *pc, int next, const uint8_t **buf, int *buf_size)
Combine the (truncated) bitstream to a complete frame.
Definition: parser.c:234
int last_frame_samples
Definition: tak.h:137
#define FFMAX(a, b)
Definition: common.h:94
#define fail()
Definition: checkasm.h:123
void ff_parse_close(AVCodecParserContext *s)
Definition: parser.c:320
int overread
the number of bytes which where irreversibly read from the next frame
Definition: parser.h:35
#define FFMIN(a, b)
Definition: common.h:96
#define s(width, name)
Definition: cbs_vp9.c:257
uint8_t * buffer
Definition: parser.h:29
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:677
ParseContext pc
Definition: tak_parser.c:32
main external API structure.
Definition: avcodec.h:526
int frame_samples
Definition: tak.h:136
TAK (Tom&#39;s lossless Audio Kompressor) decoder/demuxer common functions.
#define END_NOT_FOUND
Definition: parser.h:40
int index
Definition: parser.h:30
#define PARSER_FLAG_COMPLETE_FRAMES
Definition: avcodec.h:3391
#define TAK_MAX_FRAME_HEADER_BYTES
Definition: tak.h:96
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:3406