[FFmpeg-cvslog] avformat/aacdec: add a custom read_packet function
James Almer
git at videolan.org
Sun Jun 4 17:53:18 EEST 2017
ffmpeg | branch: master | James Almer <jamrial at gmail.com> | Fri Jun 2 20:34:24 2017 -0300| [3d4026325381c1066d771bcb83e024c92ea7e189] | committer: James Almer
avformat/aacdec: add a custom read_packet function
Atempt to read and propagate only full ADTS frames and not other data,
like id3v1 or APETags at the end of the file.
Fixes ticket #6437.
Reviewed-by: Michael Niedermayer <michael at niedermayer.cc>
Signed-off-by: James Almer <jamrial at gmail.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=3d4026325381c1066d771bcb83e024c92ea7e189
---
libavformat/aacdec.c | 44 ++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 42 insertions(+), 2 deletions(-)
diff --git a/libavformat/aacdec.c b/libavformat/aacdec.c
index 5ab5197e33..364b33404f 100644
--- a/libavformat/aacdec.c
+++ b/libavformat/aacdec.c
@@ -23,10 +23,11 @@
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
-#include "rawdec.h"
#include "id3v1.h"
#include "apetag.h"
+#define ADTS_HEADER_SIZE 7
+
static int adts_aac_probe(AVProbeData *p)
{
int max_frames = 0, first_frames = 0;
@@ -79,6 +80,7 @@ static int adts_aac_probe(AVProbeData *p)
static int adts_aac_read_header(AVFormatContext *s)
{
AVStream *st;
+ uint16_t state;
st = avformat_new_stream(s, NULL);
if (!st)
@@ -96,18 +98,56 @@ static int adts_aac_read_header(AVFormatContext *s)
avio_seek(s->pb, cur, SEEK_SET);
}
+ // skip data until the first ADTS frame is found
+ state = avio_r8(s->pb);
+ while (!avio_feof(s->pb) && avio_tell(s->pb) < s->probesize) {
+ state = (state << 8) | avio_r8(s->pb);
+ if ((state >> 4) != 0xFFF)
+ continue;
+ avio_seek(s->pb, -2, SEEK_CUR);
+ break;
+ }
+ if ((state >> 4) != 0xFFF)
+ return AVERROR_INVALIDDATA;
+
// LCM of all possible ADTS sample rates
avpriv_set_pts_info(st, 64, 1, 28224000);
return 0;
}
+static int adts_aac_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ int ret, fsize;
+
+ ret = av_get_packet(s->pb, pkt, ADTS_HEADER_SIZE);
+ if (ret < 0)
+ return ret;
+ if (ret < ADTS_HEADER_SIZE) {
+ av_packet_unref(pkt);
+ return AVERROR(EIO);
+ }
+
+ if ((AV_RB16(pkt->data) >> 4) != 0xfff) {
+ av_packet_unref(pkt);
+ return AVERROR_INVALIDDATA;
+ }
+
+ fsize = (AV_RB32(pkt->data + 3) >> 13) & 0x1FFF;
+ if (fsize < ADTS_HEADER_SIZE) {
+ av_packet_unref(pkt);
+ return AVERROR_INVALIDDATA;
+ }
+
+ return av_append_packet(s->pb, pkt, fsize - ADTS_HEADER_SIZE);
+}
+
AVInputFormat ff_aac_demuxer = {
.name = "aac",
.long_name = NULL_IF_CONFIG_SMALL("raw ADTS AAC (Advanced Audio Coding)"),
.read_probe = adts_aac_probe,
.read_header = adts_aac_read_header,
- .read_packet = ff_raw_read_partial_packet,
+ .read_packet = adts_aac_read_packet,
.flags = AVFMT_GENERIC_INDEX,
.extensions = "aac",
.mime_type = "audio/aac,audio/aacp,audio/x-aac",
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