[FFmpeg-devel] [PATCH]Support mulaw audio in Hikvision CCTV files

Carl Eugen Hoyos cehoyos at ag.or.at
Tue Mar 26 11:16:16 CET 2013


HI!

Attached patch fixes vlc ticket #8344 for me.

Please comment, Carl Eugen
-------------- next part --------------
diff --git a/libavformat/mpeg.c b/libavformat/mpeg.c
index f36f0db..8cb4a98 100644
--- a/libavformat/mpeg.c
+++ b/libavformat/mpeg.c
@@ -110,6 +110,7 @@ typedef struct MpegDemuxContext {
     unsigned char psm_es_type[256];
     int sofdec;
     int dvd;
+    int imkh_cctv;
 #if CONFIG_VOBSUB_DEMUXER
     AVFormatContext *sub_ctx;
     FFDemuxSubtitlesQueue q;
@@ -123,6 +124,9 @@ static int mpegps_read_header(AVFormatContext *s)
     int v, i = 0;
     int64_t last_pos = avio_tell(s->pb);
 
+    if (AV_RL32(s->pb->buffer) == MKTAG('I', 'M', 'K', 'H'))
+        m->imkh_cctv = 1;
+
     m->header_state = 0xff;
     s->ctx_flags |= AVFMTCTX_NOHEADER;
 
@@ -506,6 +510,9 @@ static int mpegps_read_packet(AVFormatContext *s,
         } else if(es_type == STREAM_TYPE_AUDIO_AC3){
             codec_id = AV_CODEC_ID_AC3;
             type = AVMEDIA_TYPE_AUDIO;
+        } else if(m->imkh_cctv && es_type == 0x91){
+            codec_id = AV_CODEC_ID_PCM_MULAW;
+            type = AVMEDIA_TYPE_AUDIO;
     } else if (startcode >= 0x1e0 && startcode <= 0x1ef) {
         static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 };
         unsigned char buf[8];
@@ -564,6 +571,11 @@ static int mpegps_read_packet(AVFormatContext *s,
     st->id = startcode;
     st->codec->codec_type = type;
     st->codec->codec_id = codec_id;
+    if (st->codec->codec_id == AV_CODEC_ID_PCM_MULAW) {
+        st->codec->channels = 1;
+        st->codec->channel_layout = AV_CH_LAYOUT_MONO;
+        st->codec->sample_rate = 8000;
+    }
     st->request_probe     = request_probe;
     if (codec_id != AV_CODEC_ID_PCM_S16BE)
         st->need_parsing = AVSTREAM_PARSE_FULL;


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