FFmpeg
qoi_parser.c
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1 /*
2  * QOI parser
3  * Copyright (c) 2022 Paul B Mahol
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  * QOI parser
25  */
26 
27 #include "parser.h"
28 
29 typedef struct QOIParseContext {
32 
34  const uint8_t **poutbuf, int *poutbuf_size,
35  const uint8_t *buf, int buf_size)
36 {
37  QOIParseContext *ipc = s->priv_data;
38  uint64_t state = ipc->pc.state64;
39  int next = END_NOT_FOUND, i = 0;
40 
41  s->pict_type = AV_PICTURE_TYPE_NONE;
42  s->duration = 1;
43 
44  *poutbuf_size = 0;
45  *poutbuf = NULL;
46 
47  if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
48  next = buf_size;
49  } else {
50  for (; i < buf_size; i++) {
51  state = (state << 8) | buf[i];
52  if (state == 0x01LL) {
53  next = i + 1;
54  break;
55  }
56  }
57 
58  ipc->pc.state64 = state;
59  if (ff_combine_frame(&ipc->pc, next, &buf, &buf_size) < 0) {
60  *poutbuf = NULL;
61  *poutbuf_size = 0;
62  return buf_size;
63  }
64  }
65 
66  *poutbuf = buf;
67  *poutbuf_size = buf_size;
68 
69  return next;
70 }
71 
74  .priv_data_size = sizeof(QOIParseContext),
75  .parser_parse = qoi_parse,
76  .parser_close = ff_parse_close,
77 };
ff_parse_close
void ff_parse_close(AVCodecParserContext *s)
Definition: parser.c:290
ff_qoi_parser
const AVCodecParser ff_qoi_parser
Definition: qoi_parser.c:72
ParseContext
Definition: parser.h:28
s
#define s(width, name)
Definition: cbs_vp9.c:198
NULL
#define NULL
Definition: coverity.c:32
qoi_parse
static int qoi_parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition: qoi_parser.c:33
AVCodecParser::codec_ids
int codec_ids[7]
Definition: avcodec.h:2908
AV_CODEC_ID_QOI
@ AV_CODEC_ID_QOI
Definition: codec_id.h:318
AV_PICTURE_TYPE_NONE
@ AV_PICTURE_TYPE_NONE
Undefined.
Definition: avutil.h:278
ff_combine_frame
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:203
PARSER_FLAG_COMPLETE_FRAMES
#define PARSER_FLAG_COMPLETE_FRAMES
Definition: avcodec.h:2782
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
parser.h
AVCodecParserContext
Definition: avcodec.h:2748
QOIParseContext
Definition: qoi_parser.c:29
AVCodecContext
main external API structure.
Definition: avcodec.h:451
ParseContext::state64
uint64_t state64
contains the last 8 bytes in MSB order
Definition: parser.h:37
state
static struct @463 state
END_NOT_FOUND
#define END_NOT_FOUND
Definition: parser.h:40
AVCodecParser
Definition: avcodec.h:2907
QOIParseContext::pc
ParseContext pc
Definition: qoi_parser.c:30