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 Libav.
10 * Libav 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 * Libav 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 Libav; 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)
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) {
64 } else if (!pc1->lastmarker) {
66 pc1->lastmarker = state;
73 for (; i < buf_size; i++) {
75 state = (state << 8) | buf[i];
76 if (state == DCA_HD_MARKER && !pc1->hd_pos)
77 pc1->hd_pos = pc1->size;
78 if (state == pc1->lastmarker && IS_MARKER(state, i, buf, buf_size)) {
79 if(pc1->framesize > pc1->size)
82 pc1->framesize = pc1->hd_pos ? pc1->hd_pos : pc1->size;
84 pc->frame_start_found = 0;
91 pc->frame_start_found = start_found;
96 static av_cold int dca_parse_init(AVCodecParserContext * s)
98 DCAParseContext *pc1 = s->priv_data;
104 static int dca_parse_params(const uint8_t *buf, int buf_size, int *duration,
108 uint8_t hdr[12 + FF_INPUT_BUFFER_PADDING_SIZE] = { 0 };
109 int ret, sample_blocks, sr_code;
112 return AVERROR_INVALIDDATA;
114 if ((ret = ff_dca_convert_bitstream(buf, 12, hdr, 12)) < 0)
117 init_get_bits(&gb, hdr, 96);
119 skip_bits_long(&gb, 39);
120 sample_blocks = get_bits(&gb, 7) + 1;
121 if (sample_blocks < 8)
122 return AVERROR_INVALIDDATA;
123 *duration = 256 * (sample_blocks / 8);
126 sr_code = get_bits(&gb, 4);
127 *sample_rate = avpriv_dca_sample_rates[sr_code];
128 if (*sample_rate == 0)
129 return AVERROR_INVALIDDATA;
134 static int dca_parse(AVCodecParserContext * s,
135 AVCodecContext * avctx,
136 const uint8_t ** poutbuf, int *poutbuf_size,
137 const uint8_t * buf, int buf_size)
139 DCAParseContext *pc1 = s->priv_data;
140 ParseContext *pc = &pc1->pc;
141 int next, duration, sample_rate;
143 if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
146 next = dca_find_frame_end(pc1, buf, buf_size);
148 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
155 /* read the duration and sample rate from the frame header */
156 if (!dca_parse_params(buf, buf_size, &duration, &sample_rate)) {
157 s->duration = duration;
158 avctx->sample_rate = sample_rate;
163 *poutbuf_size = buf_size;
167 AVCodecParser ff_dca_parser = {
168 .codec_ids = { AV_CODEC_ID_DTS },
169 .priv_data_size = sizeof(DCAParseContext),
170 .parser_init = dca_parse_init,
171 .parser_parse = dca_parse,
172 .parser_close = ff_parse_close,