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[vdr] Re: Slowmotion



Hi,

Stefan Lucke wrote:

On Donnerstag, 3. Juni 2004 19:28, Klaus Schmidinger wrote:

From the comment:

     ///< Sets the device into a mode where replay is done slower.
     ///< Every single frame shall then be displayed the given number of
     ///< times.

This means that it will only be called for slow motion ("Sets the device
into a mode where replay is done _slower_") and that higher numbers mean
slower replay (ok, maybe the name "Speed" is badly chosen...).
So my observation is different. I added speed number output to softdevice's
not implementet function TrickSpeed and got the following results:

keys: ff fast forward, fr fast rewind

from play:
key	Speed	OSD
ff	6	1>>
ff	3	2>>
ff	1	3>>

from play:
fr      6       <<1
fr      3       <<2
fr      1       <<3

from pause:
ff      8       1|>
ff      4       2|>
ff      2       3|>
ff should be sf (slow forward).

from pause:
fr      63      <|1
fr      48      <|2
fr      24      <|3
fr should be sr (slow reverse).

Those slow back numbers I don't understand. 63 times presenting a decoded picture ?
Or 63 times feeding the decoder with some data to get some decoded pictures out ?
For slow reverse, VDR only sends I frames to the device. Therefore, the I frame needs to be displayed for additional 11 frames (the missing B and P frames), which makes a total of 12 frame times. That's why the sr values are twelve times higher than those of sf, and it seems, that the hardware decoders allow only a maximum frame repetation value of 63.

For stillpicture display I had to push 1 I-frame 4 times to ffmpeg to get one decoded.
That's true for the vdr-xine device too, although there 3 repetitions are enough.

Bye.
--
Dipl.-Inform. (FH) Reinhard Nissl
mailto:rnissl@gmx.de




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