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-rw-r--r--libavformat/dtsdec.c94
1 files changed, 75 insertions, 19 deletions
diff --git a/libavformat/dtsdec.c b/libavformat/dtsdec.c
index 90e9d38582..da0fb61a60 100644
--- a/libavformat/dtsdec.c
+++ b/libavformat/dtsdec.c
@@ -2,25 +2,27 @@
* RAW DTS demuxer
* Copyright (c) 2008 Benjamin Larsson
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavcodec/bytestream.h"
+#include "libavcodec/dca.h"
#include "libavcodec/dca_syncwords.h"
+#include "libavcodec/get_bits.h"
#include "avformat.h"
#include "rawdec.h"
@@ -29,34 +31,88 @@ static int dts_probe(AVProbeData *p)
{
const uint8_t *buf, *bufp;
uint32_t state = -1;
- int markers[3] = {0};
- int sum, max;
+ int markers[4*16] = {0};
+ int sum, max, i;
+ int64_t diff = 0;
+ uint8_t hdr[12 + FF_INPUT_BUFFER_PADDING_SIZE] = { 0 };
- buf = p->buf;
+ buf = p->buf + FFMIN(4096, p->buf_size);
for(; buf < (p->buf+p->buf_size)-2; buf+=2) {
+ int marker, sample_blocks, sample_rate, sr_code, framesize;
+ int lfe;
+ GetBitContext gb;
+
bufp = buf;
state = (state << 16) | bytestream_get_be16(&bufp);
+ if (buf - p->buf >= 4)
+ diff += FFABS(((int16_t)AV_RL16(buf)) - (int16_t)AV_RL16(buf-4));
+
/* regular bitstream */
- if (state == DCA_SYNCWORD_CORE_BE || state == DCA_SYNCWORD_CORE_LE)
- markers[0]++;
+ if (state == DCA_SYNCWORD_CORE_BE &&
+ (bytestream_get_be16(&bufp) & 0xFC00) == 0xFC00)
+ marker = 0;
+ else if (state == DCA_SYNCWORD_CORE_LE &&
+ (bytestream_get_be16(&bufp) & 0x00FC) == 0x00FC)
+ marker = 1;
/* 14 bits big-endian bitstream */
- if (state == DCA_SYNCWORD_CORE_14B_BE)
- if ((bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
- markers[1]++;
+ else if (state == DCA_SYNCWORD_CORE_14B_BE &&
+ (bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
+ marker = 2;
/* 14 bits little-endian bitstream */
- if (state == DCA_SYNCWORD_CORE_14B_LE)
- if ((bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007)
- markers[2]++;
+ else if (state == DCA_SYNCWORD_CORE_14B_LE &&
+ (bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007)
+ marker = 3;
+ else
+ continue;
+
+ if (avpriv_dca_convert_bitstream(buf-2, 12, hdr, 12) < 0)
+ continue;
+
+ init_get_bits(&gb, hdr, 96);
+ skip_bits_long(&gb, 39);
+
+ sample_blocks = get_bits(&gb, 7) + 1;
+ if (sample_blocks < 8)
+ continue;
+
+ framesize = get_bits(&gb, 14) + 1;
+ if (framesize < 95)
+ continue;
+
+ skip_bits(&gb, 6);
+ sr_code = get_bits(&gb, 4);
+ sample_rate = avpriv_dca_sample_rates[sr_code];
+ if (sample_rate == 0)
+ continue;
+
+ get_bits(&gb, 5);
+ if (get_bits(&gb, 1))
+ continue;
+
+ skip_bits_long(&gb, 9);
+ lfe = get_bits(&gb, 2);
+ if (lfe > 2)
+ continue;
+
+ marker += 4* sr_code;
+
+ markers[marker] ++;
}
- sum = markers[0] + markers[1] + markers[2];
- max = markers[1] > markers[0];
- max = markers[2] > markers[max] ? 2 : max;
+
+ sum = max = 0;
+ for (i=0; i<FF_ARRAY_ELEMS(markers); i++) {
+ sum += markers[i];
+ if (markers[max] < markers[i])
+ max = i;
+ }
+
if (markers[max] > 3 && p->buf_size / markers[max] < 32*1024 &&
- markers[max] * 4 > sum * 3)
+ markers[max] * 4 > sum * 3 &&
+ diff / p->buf_size > 200)
return AVPROBE_SCORE_EXTENSION + 1;
return 0;