[vdr] How to convert a JPEG image to an I-frame?

Klaus Schmidinger Klaus.Schmidinger at cadsoft.de
Sun Nov 11 15:30:54 CET 2007

On 11/11/07 15:20, Reinhard Nissl wrote:
> Hi,
> Klaus Schmidinger schrieb:
>> When I display a picture generated with this script through a call
>> to DeviceStillPicture(), the display looks very nice for a short while,
>> and after that slanted lines get jagged. It appears as if the two
>> interlaced half-pictures are first sent in turn, and finally only
>> one of them is displayed continuously.
>> Calling DeviceStillPicture() repeatedly in a loop results in the
>> display jumping between "nice" and "jagged".
>> So I thought about sending the picture file to the device through
>> cPlayer::PlayPes() in a continuous loop. For that purpose I have
>> added a call to 'mplex' to the script, as can be seen in the attachment.
>> When I display such a still file on a FF DVB card by calling cPlayer::PlayPes()
>> in a continuous loop, the image on the tv screen looks like it is
>> displaying both interlaced half-pictures in turn, but it is "jumpy" (as if
>> the time between displaying the two half pictures is too long).
>> Does anybody have an idea how this could be improved, so that
>> I get a smooth display, with slanted lines not jagged (just as if
>> a still picture was shown in a normal movie)?
> How does the attached PES file look like? In vdr-xine, I send it just
> once and it looks OK in xine.
> When it looks ok, I'll have to search for the commands which created it ;-)
> I think, I had specified an option to create progressive frames.

After running your file through

  mplex -f 7 -o test.mpg noSignal.mpg

and displaying test.mpg trough cPlayer::PlayPes() I get a pefectly
smooth display.

Would be great if you could find the commands that created this one.


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