Author Topic: Videostream 720p  (Read 7485 times)

Jan Gruuthuse

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Videostream 720p
« on: March 19, 2012, 02:06:29 PM »
To my amazement when copying 720p Video Stream from MPEG-TS container to another container the videostream is decreased by 2662 kbps
The TS files are the source videos. 1.2 GB is saved by just copying from .TS to .MKV? Can you verify my results and do some testing to confirm.



The source video:


The copied video (not re-encoded):


Download test.ts 17.32 MB 10 second 720p video https://rapidshare.com/files/2781140509/test.ts
« Last Edit: March 19, 2012, 02:12:23 PM by Jan Gruuthuse »

mean

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Re: Videostream 720p
« Reply #1 on: March 19, 2012, 03:14:44 PM »
TS byt itself is adding a lot of overhead
H264 in addition has filler NALU that are removed by avidemux

Jan Gruuthuse

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Re: Videostream 720p
« Reply #2 on: March 19, 2012, 04:07:33 PM »
Thanks for explaining, was worried essential data was lost. So only NALU fill 0xFF Bytes are removed from the stream and not the overflow data that could be needed? But not when copying from MPEG-TS to MPEG-TS? Like in my case going from MPEG-TS .TRP to  MPEG-TS .TS?

mean

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Re: Videostream 720p
« Reply #3 on: March 19, 2012, 04:57:13 PM »
The other possibility is that your source is really CBR
That is if there is not enough data, padding is added to make sure that the overall bitrate is somehow constant

By default avidemux TS muxer is in VBR mode, so the overall bitrate will vary depending on the source

Please note that the statement in the previous post only applies to TS->MKV, TS->TS will recreate the overhead and filler NALU

Jan Gruuthuse

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Re: Videostream 720p
« Reply #4 on: March 19, 2012, 05:44:10 PM »
Please note that the statement in the previous post only applies to TS->MKV, TS->TS will recreate the overhead and filler NALU
Behavior is same when copy video .TS -> AVI or  .TS -> MP4 container, significant decrease.

Think this is VBR?

DTV scan technical info: DVB-S2 FTA arte HD 19°East MPEG4

« Last Edit: March 19, 2012, 05:48:07 PM by Jan Gruuthuse »

nibbles

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Re: Videostream 720p
« Reply #5 on: March 19, 2012, 07:40:20 PM »
@jan when you post your MediaInfo output, switch to the html view and use that.  The summary is a little sparse on the details.

Jan Gruuthuse

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Re: Videostream 720p
« Reply #6 on: March 20, 2012, 09:46:28 AM »
When using HTML, not all info is showing on screen, for one reason or another, you can't save HTML output (v0.7.50) linux. Last line in 1st posting provided downlink to the used source video sample used to create the avi, mkv and mp4. Was only 18 MB download. Big difference was the filesize

nibbles

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Re: Videostream 720p
« Reply #7 on: March 21, 2012, 04:15:15 AM »
This test.ts generated so much output in MediaInfo that I had to switch to Text mode.
No copy and paste in linux?  This is what it said.