@@ -7,6 +7,7 @@ version next:

 - SBaGen (SBG) binaural beats script demuxer

 - OpenMG Audio muxer

 - SMJPEG demuxer

+- dv: add timecode to metadata

 version 0.9:

@@ -87,6 +87,9 @@ static const uint8_t* dv_extract_pack(uint8_t* frame, enum dv_pack_type t)

     case dv_video_control:

         offs = (80*5 + 48 + 5);

         break;

+    case dv_timecode:

+        offs = (80*1 + 3 + 3);

+        break;

     default:

         return NULL;

     }

@@ -267,6 +270,45 @@ static int dv_extract_video_info(DVDemuxContext *c, uint8_t* frame)

     return size;

 }

+static int bcd2int(uint8_t bcd)

+{

+   int low  = bcd & 0xf;

+   int high = bcd >> 4;

+   if (low > 9 || high > 9)

+       return -1;

+   return low + 10*high;

+}

+

+static int dv_extract_timecode(DVDemuxContext* c, uint8_t* frame, char tc[32])

+{

+    int hh, mm, ss, ff, drop_frame;

+    const uint8_t *tc_pack;

+

+    tc_pack = dv_extract_pack(frame, dv_timecode);

+    if (!tc_pack)

+        return 0;

+

+    ff = bcd2int(tc_pack[1] & 0x3f);

+    ss = bcd2int(tc_pack[2] & 0x7f);

+    mm = bcd2int(tc_pack[3] & 0x7f);

+    hh = bcd2int(tc_pack[4] & 0x3f);

+    drop_frame = tc_pack[1] >> 6 & 0x1;

+

+    if (ff < 0 || ss < 0 || mm < 0 || hh < 0)

+        return -1;

+

+    // For PAL systems, drop frame bit is replaced by an arbitrary

+    // bit so its value should not be considered. Drop frame timecode

+    // is only relevant for NTSC systems.

+    if(c->sys->ltc_divisor == 25 || c->sys->ltc_divisor == 50) {

+        drop_frame = 0;

+    }

+

+    snprintf(tc, 32, "%02d:%02d:%02d%c%02d",

+             hh, mm, ss, drop_frame ? ';' : ':', ff);

+    return 1;

+}

+

 /*

  * The following 3 functions constitute our interface to the world

  */

@@ -404,6 +446,38 @@ typedef struct RawDVContext {

     uint8_t         buf[DV_MAX_FRAME_SIZE];

 } RawDVContext;

+static int dv_read_timecode(AVFormatContext *s) {

+    int ret;

+    char timecode[32];

+    int64_t pos = avio_tell(s->pb);

+

+    // Read 3 DIF blocks: Header block and 2 Subcode blocks.

+    int partial_frame_size = 3 * 80;

+    uint8_t *partial_frame = av_mallocz(sizeof(*partial_frame) *

+                                        partial_frame_size);

+

+    RawDVContext *c = s->priv_data;

+    ret = avio_read(s->pb, partial_frame, partial_frame_size);

+    if (ret < 0)

+        goto finish;

+

+    if (ret < partial_frame_size) {

+        ret = -1;

+        goto finish;

+    }

+

+    ret = dv_extract_timecode(c->dv_demux, partial_frame, timecode);

+    if (ret)

+        av_dict_set(&s->metadata, "timecode", timecode, 0);

+    else if (ret < 0)

+        av_log(s, AV_LOG_ERROR, "Detected timecode is invalid");

+

+finish:

+    av_free(partial_frame);

+    avio_seek(s->pb, pos, SEEK_SET);

+    return ret;

+}

+

 static int dv_read_header(AVFormatContext *s,

                           AVFormatParameters *ap)

 {

@@ -444,6 +518,9 @@ static int dv_read_header(AVFormatContext *s,

     s->bit_rate = av_rescale_q(c->dv_demux->sys->frame_size, (AVRational){8,1},

                                c->dv_demux->sys->time_base);

+    if (s->pb->seekable)

+        dv_read_timecode(s);

+

     return 0;

 }