1 files changed, 73 insertions, 19 deletions

diff --git a/libavformat/dtsdec.c b/libavformat/dtsdec.c
index 9010711599..d054f43537 100644
--- a/libavformat/dtsdec.c
+++ b/libavformat/dtsdec.c
@@ -2,24 +2,26 @@
  * 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/get_bits.h"
+#include "libavcodec/dca.h"
 #include "avformat.h"
 #include "rawdec.h"
 
@@ -32,34 +34,86 @@ 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_MARKER_RAW_BE || state == DCA_MARKER_RAW_LE)
-            markers[0]++;
+        if (state == DCA_MARKER_RAW_BE)
+            marker = 0;
+        else if (state == DCA_MARKER_RAW_LE)
+            marker = 1;
 
         /* 14 bits big-endian bitstream */
-        if (state == DCA_MARKER_14B_BE)
-            if ((bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
-                markers[1]++;
+        else if (state == DCA_MARKER_14B_BE &&
+                 (bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
+            marker = 2;
 
         /* 14 bits little-endian bitstream */
-        if (state == DCA_MARKER_14B_LE)
-            if ((bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007)
-                markers[2]++;
+        else if (state == DCA_MARKER_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;