3 * Copyright (C) 2004 Gildas Bazin
4 * Copyright (C) 2004 Benjamin Zores
5 * Copyright (C) 2006 Benjamin Larsson
6 * Copyright (C) 2007 Konstantin Shishkov
8 * This file is part of FFmpeg.
10 * FFmpeg is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
15 * FFmpeg is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 typedef struct DCAParseContext
{
37 #define IS_MARKER(state, i, buf, buf_size) \
38 ((state == DCA_MARKER_14B_LE && (i < buf_size - 2) && (buf[i + 1] & 0xF0) == 0xF0 && buf[i + 2] == 0x07) || \
39 (state == DCA_MARKER_14B_BE && (i < buf_size - 2) && buf[i + 1] == 0x07 && (buf[i + 2] & 0xF0) == 0xF0) || \
40 state == DCA_MARKER_RAW_LE || state == DCA_MARKER_RAW_BE || state == DCA_HD_MARKER)
43 * Find the end of the current frame in the bitstream.
44 * @return the position of the first byte of the next frame, or -1
46 static int dca_find_frame_end(DCAParseContext
*pc1
, const uint8_t *buf
,
51 ParseContext
*pc
= &pc1
->pc
;
53 start_found
= pc
->frame_start_found
;
58 for (i
= 0; i
< buf_size
; i
++) {
59 state
= (state
<< 8) | buf
[i
];
60 if (IS_MARKER(state
, i
, buf
, buf_size
)) {
61 if (!pc1
->lastmarker
|| state
== pc1
->lastmarker
|| pc1
->lastmarker
== DCA_HD_MARKER
) {
63 pc1
->lastmarker
= state
;
71 for (; i
< buf_size
; i
++) {
73 state
= (state
<< 8) | buf
[i
];
74 if (state
== DCA_HD_MARKER
&& !pc1
->hd_pos
)
75 pc1
->hd_pos
= pc1
->size
;
76 if (IS_MARKER(state
, i
, buf
, buf_size
) && (state
== pc1
->lastmarker
|| pc1
->lastmarker
== DCA_HD_MARKER
)) {
77 if (pc1
->framesize
> pc1
->size
)
79 pc
->frame_start_found
= 0;
86 pc
->frame_start_found
= start_found
;
91 static av_cold
int dca_parse_init(AVCodecParserContext
*s
)
93 DCAParseContext
*pc1
= s
->priv_data
;
99 static int dca_parse_params(const uint8_t *buf
, int buf_size
, int *duration
,
100 int *sample_rate
, int *framesize
)
103 uint8_t hdr
[12 + FF_INPUT_BUFFER_PADDING_SIZE
] = { 0 };
104 int ret
, sample_blocks
, sr_code
;
107 return AVERROR_INVALIDDATA
;
109 if ((ret
= avpriv_dca_convert_bitstream(buf
, 12, hdr
, 12)) < 0)
112 init_get_bits(&gb
, hdr
, 96);
114 skip_bits_long(&gb
, 39);
115 sample_blocks
= get_bits(&gb
, 7) + 1;
116 if (sample_blocks
< 8)
117 return AVERROR_INVALIDDATA
;
118 *duration
= 256 * (sample_blocks
/ 8);
120 *framesize
= get_bits(&gb
, 14) + 1;
122 return AVERROR_INVALIDDATA
;
125 sr_code
= get_bits(&gb
, 4);
126 *sample_rate
= avpriv_dca_sample_rates
[sr_code
];
127 if (*sample_rate
== 0)
128 return AVERROR_INVALIDDATA
;
133 static int dca_parse(AVCodecParserContext
*s
, AVCodecContext
*avctx
,
134 const uint8_t **poutbuf
, int *poutbuf_size
,
135 const uint8_t *buf
, int buf_size
)
137 DCAParseContext
*pc1
= s
->priv_data
;
138 ParseContext
*pc
= &pc1
->pc
;
139 int next
, duration
, sample_rate
;
141 if (s
->flags
& PARSER_FLAG_COMPLETE_FRAMES
) {
144 next
= dca_find_frame_end(pc1
, buf
, buf_size
);
146 if (ff_combine_frame(pc
, next
, &buf
, &buf_size
) < 0) {
153 /* read the duration and sample rate from the frame header */
154 if (!dca_parse_params(buf
, buf_size
, &duration
, &sample_rate
, &pc1
->framesize
)) {
155 s
->duration
= duration
;
156 avctx
->sample_rate
= sample_rate
;
161 *poutbuf_size
= buf_size
;
165 AVCodecParser ff_dca_parser
= {
166 .codec_ids
= { AV_CODEC_ID_DTS
},
167 .priv_data_size
= sizeof(DCAParseContext
),
168 .parser_init
= dca_parse_init
,
169 .parser_parse
= dca_parse
,
170 .parser_close
= ff_parse_close
,