Merge commit '50a1c66cf6ab7eb683daaa9e2da3869fa3a54609'

* commit '50a1c66cf6ab7eb683daaa9e2da3869fa3a54609':
  ac3_parser: add a public function for parsing the data required by the demuxer

avpriv_ac3_parse_header() is left in place but without the
GetBitContext parameter, as the mov muxer requires a lot more fields
than just bitstream_id and frame_size from the AC3HeaderInfo struct.

Merged-by: James Almer <jamrial@gmail.com>

2 files changed, 29 insertions, 22 deletions

diff --git a/libavformat/ac3dec.c b/libavformat/ac3dec.c
index e85b0ac7c9..8ea73824a6 100644
--- a/libavformat/ac3dec.c
+++ b/libavformat/ac3dec.c
@@ -19,6 +19,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include "libavutil/avassert.h"
 #include "libavutil/crc.h"
 #include "libavcodec/ac3_parser.h"
 #include "avformat.h"
@@ -28,8 +29,6 @@ static int ac3_eac3_probe(AVProbeData *p, enum AVCodecID expected_codec_id)
 {
     int max_frames, first_frames = 0, frames;
     const uint8_t *buf, *buf2, *end;
-    AC3HeaderInfo *phdr = NULL;
-    GetBitContext gbc;
     enum AVCodecID codec_id = AV_CODEC_ID_AC3;
 
     max_frames = 0;
@@ -44,7 +43,10 @@ static int ac3_eac3_probe(AVProbeData *p, enum AVCodecID expected_codec_id)
 
         for(frames = 0; buf2 < end; frames++) {
             uint8_t buf3[4096];
-            int i;
+            uint8_t bitstream_id;
+            uint16_t frame_size;
+            int i, ret;
+
             if(!memcmp(buf2, "\x1\x10\0\0\0\0\0\0", 8))
                 buf2+=16;
             if (buf[0] == 0x77 && buf[1] == 0x0B) {
@@ -52,31 +54,35 @@ static int ac3_eac3_probe(AVProbeData *p, enum AVCodecID expected_codec_id)
                     buf3[i  ] = buf2[i+1];
                     buf3[i+1] = buf2[i  ];
                 }
-                init_get_bits(&gbc, buf3, 54);
+                ret = av_ac3_parse_header(buf3, 8, &bitstream_id,
+                                          &frame_size);
             }else
-                init_get_bits(&gbc, buf2, 54);
-            if(avpriv_ac3_parse_header(&gbc, &phdr) < 0)
+                ret = av_ac3_parse_header(buf2, end - buf2, &bitstream_id,
+                                          &frame_size);
+            if (ret < 0)
                 break;
-            if(buf2 + phdr->frame_size > end)
+            if(buf2 + frame_size > end)
                 break;
             if (buf[0] == 0x77 && buf[1] == 0x0B) {
-                av_assert0(phdr->frame_size <= sizeof(buf3));
-                for(i=8; i<phdr->frame_size; i+=2) {
+                av_assert0(frame_size <= sizeof(buf3));
+                for(i = 8; i < frame_size; i += 2) {
                     buf3[i  ] = buf2[i+1];
                     buf3[i+1] = buf2[i  ];
                 }
+                if (av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, buf3 + 2, frame_size - 2))
+                    break;
+            } else {
+                if (av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, buf2 + 2, frame_size - 2))
+                    break;
             }
-            if(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, gbc.buffer + 2, phdr->frame_size - 2))
-                break;
-            if (phdr->bitstream_id > 10)
+            if (bitstream_id > 10)
                 codec_id = AV_CODEC_ID_EAC3;
-            buf2 += phdr->frame_size;
+            buf2 += frame_size;
         }
         max_frames = FFMAX(max_frames, frames);
         if(buf == p->buf)
             first_frames = frames;
     }
-    av_freep(&phdr);
     if(codec_id != expected_codec_id) return 0;
     // keep this in sync with mp3 probe, both need to avoid
     // issues with MPEG-files!
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index 2838286141..a34987a7dc 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -31,7 +31,7 @@
 #include "avio.h"
 #include "isom.h"
 #include "avc.h"
-#include "libavcodec/ac3_parser.h"
+#include "libavcodec/ac3_parser_internal.h"
 #include "libavcodec/dnxhddata.h"
 #include "libavcodec/flac.h"
 #include "libavcodec/get_bits.h"
@@ -345,7 +345,6 @@ struct eac3_info {
 #if CONFIG_AC3_PARSER
 static int handle_eac3(MOVMuxContext *mov, AVPacket *pkt, MOVTrack *track)
 {
-    GetBitContext gbc;
     AC3HeaderInfo tmp, *hdr = &tmp;
     struct eac3_info *info;
     int num_blocks;
@@ -354,8 +353,7 @@ static int handle_eac3(MOVMuxContext *mov, AVPacket *pkt, MOVTrack *track)
         return AVERROR(ENOMEM);
     info = track->eac3_priv;
 
-    init_get_bits(&gbc, pkt->data, pkt->size * 8);
-    if (avpriv_ac3_parse_header(&gbc, &hdr) < 0) {
+    if (avpriv_ac3_parse_header(&hdr, pkt->data, pkt->size) < 0) {
         /* drop the packets until we see a good one */
         if (!track->entry) {
             av_log(mov, AV_LOG_WARNING, "Dropping invalid packet from start of the stream\n");
@@ -403,16 +401,18 @@ static int handle_eac3(MOVMuxContext *mov, AVPacket *pkt, MOVTrack *track)
             int parent = hdr->substreamid;
 
             while (cumul_size != pkt->size) {
-                int i;
-                init_get_bits(&gbc, pkt->data + cumul_size, (pkt->size - cumul_size) * 8);
-                if (avpriv_ac3_parse_header(&gbc, &hdr) < 0)
+                GetBitContext gbc;
+                int i, ret;
+                ret = avpriv_ac3_parse_header(&hdr, pkt->data + cumul_size, pkt->size - cumul_size);
+                if (ret < 0)
                     return AVERROR_INVALIDDATA;
                 if (hdr->frame_type != EAC3_FRAME_TYPE_DEPENDENT)
                     return AVERROR(EINVAL);
-                cumul_size += hdr->frame_size;
                 info->substream[parent].num_dep_sub++;
+                ret /= 8;
 
                 /* header is parsed up to lfeon, but custom channel map may be needed */
+                init_get_bits8(&gbc, pkt->data + cumul_size + ret, pkt->size - cumul_size - ret);
                 /* skip bsid */
                 skip_bits(&gbc, 5);
                 /* skip volume control params */
@@ -427,6 +427,7 @@ static int handle_eac3(MOVMuxContext *mov, AVPacket *pkt, MOVTrack *track)
                     info->substream[parent].chan_loc |= (get_bits(&gbc, 16) >> 5) & 0x1f;
                 else
                     info->substream[parent].chan_loc |= hdr->channel_mode;
+                cumul_size += hdr->frame_size;
             }
         }
     }