alpha/pixblockdsp: move code out of dsputil
[ffmpeg.git] / libavcodec / tak_parser.c
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 #include "tak.h"
28 #include "parser.h"
29
30 typedef struct TAKParseContext {
31     ParseContext  pc;
32     TAKStreamInfo ti;
33     int           index;
34 } TAKParseContext;
35
36 static int tak_parse(AVCodecParserContext *s, AVCodecContext *avctx,
37                      const uint8_t **poutbuf, int *poutbuf_size,
38                      const uint8_t *buf, int buf_size)
39 {
40     TAKParseContext *t = s->priv_data;
41     ParseContext *pc   = &t->pc;
42     int next           = END_NOT_FOUND;
43     GetBitContext gb;
44     int consumed = 0;
45     int needed   = buf_size ? TAK_MAX_FRAME_HEADER_BYTES : 8;
46
47     if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
48         TAKStreamInfo ti;
49         init_get_bits(&gb, buf, buf_size);
50         if (!ff_tak_decode_frame_header(avctx, &gb, &ti, 127))
51             s->duration = t->ti.last_frame_samples ? t->ti.last_frame_samples
52                                                    : t->ti.frame_samples;
53         *poutbuf      = buf;
54         *poutbuf_size = buf_size;
55         return buf_size;
56     }
57
58     while (buf_size || t->index + needed <= pc->index) {
59         if (buf_size && t->index + TAK_MAX_FRAME_HEADER_BYTES > pc->index) {
60             int tmp_buf_size       = FFMIN(2 * TAK_MAX_FRAME_HEADER_BYTES,
61                                            buf_size);
62             const uint8_t *tmp_buf = buf;
63
64             if (ff_combine_frame(pc, END_NOT_FOUND, &tmp_buf, &tmp_buf_size) != -1)
65                 return AVERROR(ENOMEM);
66             consumed += tmp_buf_size;
67             buf      += tmp_buf_size;
68             buf_size -= tmp_buf_size;
69         }
70
71         for (; t->index + needed <= pc->index; t->index++) {
72             if (pc->buffer[ t->index     ] == 0xFF &&
73                 pc->buffer[ t->index + 1 ] == 0xA0) {
74                 TAKStreamInfo ti;
75
76                 init_get_bits(&gb, pc->buffer + t->index,
77                               8 * (pc->index - t->index));
78                 if (!ff_tak_decode_frame_header(avctx, &gb,
79                         pc->frame_start_found ? &ti : &t->ti, 127) &&
80                     !ff_tak_check_crc(pc->buffer + t->index,
81                                       get_bits_count(&gb) / 8)) {
82                     if (!pc->frame_start_found) {
83                         pc->frame_start_found = 1;
84                         s->duration           = t->ti.last_frame_samples ?
85                                                 t->ti.last_frame_samples :
86                                                 t->ti.frame_samples;
87                         s->key_frame          = !!(t->ti.flags & TAK_FRAME_FLAG_HAS_INFO);
88                     } else {
89                         pc->frame_start_found = 0;
90                         next                  = t->index - pc->index;
91                         t->index              = 0;
92                         goto found;
93                     }
94                 }
95             }
96         }
97     }
98 found:
99
100     if (consumed && !buf_size && next == END_NOT_FOUND ||
101         ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
102         *poutbuf      = NULL;
103         *poutbuf_size = 0;
104         return buf_size + consumed;
105     }
106
107     if (next != END_NOT_FOUND) {
108         next        += consumed;
109         pc->overread = FFMAX(0, -next);
110     }
111
112     *poutbuf      = buf;
113     *poutbuf_size = buf_size;
114     return next;
115 }
116
117 AVCodecParser ff_tak_parser = {
118     .codec_ids      = { AV_CODEC_ID_TAK },
119     .priv_data_size = sizeof(TAKParseContext),
120     .parser_parse   = tak_parse,
121     .parser_close   = ff_parse_close,
122 };