demux_real.c: better a/v sync part 2.

cook audio frames are fairly long (almost 2 seconds). For obfuscation
purposes, they are sent as multiple fragments in intentionally wrong order.
The first sent fragment has the timestamp for the whole frame.
Sometimes, the remaining fragments carry fake timestamps interpolated across
the frame duration. Let's be careful not to trap metronom into a big lag.

1 files changed, 31 insertions, 1 deletions

diff --git a/src/demuxers/demux_real.c b/src/demuxers/demux_real.c
index 01efe3b1c..e3273f9d3 100644
--- a/src/demuxers/demux_real.c
+++ b/src/demuxers/demux_real.c
@@ -122,6 +122,7 @@ typedef struct {
   uint8_t             *frame_buffer;
   uint32_t             frame_num_bytes;
   uint32_t             sub_packet_cnt;
+  uint32_t             audio_time;
 } real_stream_t;
 
 typedef struct {
@@ -1089,7 +1090,7 @@ static int demux_real_send_chunk(demux_plugin_t *this_gen) {
   const uint16_t stream   = _X_BE_16(&header[4]);
   const off_t offset __attr_unused = this->input->get_current_pos(this->input);
   uint16_t size     = _X_BE_16(&header[2]) - DATA_PACKET_HEADER_SIZE;
-  const uint32_t timestamp= _X_BE_32(&header[6]);
+  uint32_t timestamp= _X_BE_32(&header[6]);
   int64_t pts      = (int64_t) timestamp * 90;
 
   /* Data packet header with version 1 contains 1 extra byte */
@@ -1339,6 +1340,35 @@ static int demux_real_send_chunk(demux_plugin_t *this_gen) {
     else
       this->audio_need_keyframe = 0;
 
+    /* speed up when not debugging */
+    if (this->stream->xine->verbosity == XINE_VERBOSITY_DEBUG + 1) {
+      xprintf (this->stream->xine, XINE_VERBOSITY_DEBUG + 1,
+        "demux_real: audio pts: %d.%03d %s%s\n",
+        timestamp / 1000, timestamp % 1000,
+        keyframe ? "*" : " ",
+        this->audio_stream->sub_packet_cnt ? " " : "s");
+    }
+
+    /* cook audio frames are fairly long (almost 2 seconds). For obfuscation
+       purposes, they are sent as multiple fragments in intentionally wrong order.
+       The first sent fragment has the timestamp for the whole frame.
+
+       Sometimes, the remaining fragments all carry the same time, and appear
+       immediately thereafter. This is easy.
+
+       Sometimes, the remaining fragments carry fake timestamps interpolated across
+       the frame duration. Consequently, they will be muxed between the next few
+       video frames. We get the complete frame ~2 seconds late. This is ugly.
+       Let's be careful not to trap metronom into a big lag. */
+    if (!this->audio_stream->sub_packet_cnt)
+      this->audio_stream->audio_time = timestamp;
+    else
+      timestamp = this->audio_stream->audio_time;
+    /* nasty kludge, maybe this is somewhere in mdpr? */
+    if (this->audio_stream->buf_type == BUF_AUDIO_COOK)
+      timestamp += 120;
+    pts = (int64_t) timestamp * 90;
+
     /* if we have a seekable stream then use the timestamp for the data
      * packet for more accurate seeking - if not then estimate time using
      * average bitrate */