Summary is that the error message is due to lack of keyframes and the workaround is to use Transcode.
BUT hopefully a better solution with the Render format parameters can be found. The render fix for h264/h265 formats is the addition of the lines below (which obviously is not pertinent to av1). I will see if I can find an alternative, but might not.
# use framerate for 1 keyframe/sec, needed for seeks
keyint_min=25 (or keyint_min=30 for x265)
x264-params=keyint=25 (or x265-params-keyint=30 for x265)
About the error message:
FFStream::seek:
/run/media/terje/Videoklipp/Cineform/av1_yuv422p10le_LP.webm
retry limit, pos=207
tstmp=8280, err: Input/output error
** seek fail 207,
8280
Seeking Issues (
https://cinelerra-gg.org/download/CinelerraGG_Manual/Seeking_Issues.html)
If you have an issue playing a video and not seeing it in the Compositor (just see a black
screen), it is most likely due to the media not being designed to be editable. It is most likely
not damaged. Generally it just does not have keyframes which are needed for seeking
which is what is done when you move around the media and start playing in the middle.
The media plays just fine in the compositor if you always play from the beginning because
then you don’t need keyframes to seek. You can get around this problem if you proxy the
media. A good choice to use for the proxy would be use scalar, ffmpeg/mp4 and size of 1/2.
The proxied media can then seek and you will see it play in the compositor because keyframes exist.
Or use TRANSCODE which adds keyframes when media is not seekable (see Manual for details). This is particularly useful for the mkv container, which often has seek problems.
Just a reminder about the message below.
FFMPEG::open_decoder:
some stream times estimated:
This
is not a problem. Basically, when you open a file if a stream has a
known duration, there is no message. If the duration is unknown, it is
estimated by using the File Size and Bitrate to estimate the duration.
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