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Hi,
As I told you earlier this year, I’m trying to build a plugin for my MPEG2 card. This card needs to be fed with two elementary streams with PTS/DTS information.
I was quite successful except for to things : -1- there is a difference between a VDR recording and live TV. -2- I have some audio/video synch problems
--1-- I said on this list that there is a big difference between live TV and a recording.
LiveTV is broken (on my MPEG2 card) when I use the standard MPEG2 mode. Recordings are perfects.
Here are the differences between Streaming_mode and MPEG2_mode (taken from the doc) : - streaming_mode : force the decoder to accept and use IBLOCKS - mpeg2_mode : force the decoder to accept and use IFRAMES
So it seems that LiveTV uses IBLOCKS and Recordings use IFRAMES.
Can anyone help me to understand the difference between IBLOCKS and IFRAMES ?
Is there a way to use the remux tools used by the recording feature inside my device plugin ? I would like to remux the stream before feeding the decoder to have data like in recording.
--2-- I tried several tricks to have a perfect synchro between audio and video but I wasn’t successfull.
- I set the PTS for the audio and the video. (didn’t worked) - I set the PTS and DTS (when available) for audio and video. (didn’t worked)
I always have a delay between the audio and the video is always the same (for a single channel) : - channel1 : delay = 25ms - channel2 : delay = -15ms - channel3 : delay = 0ms - …
I think this delay exists somewhere in the stream but I wasn’t able to find it. If someone can help me.
Thank you
Philippe |