Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
>This unfortunately doesn't show up in the comment (I hoped the comment would >contain the encoder string). There are different ways to fix this, >ideally >you would be able to find out if the comment for this sensor always has the >same content. Ok, I will check if the comments are always the same and let you know. Thanks, Fabian ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
2018-09-20 17:30 GMT+02:00, Fabian Kurt : > It's a FirstSensor DC3K-2-EAP This unfortunately doesn't show up in the comment (I hoped the comment would contain the encoder string). There are different ways to fix this, ideally you would be able to find out if the comment for this sensor always has the same content. An option to ignore jpg comments would of course be the simple solution but auto-detecting the issue is always better. Carl Eugen ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
It's a FirstSensor DC3K-2-EAP ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
2018-09-19 8:40 GMT+02:00, Fabian Kurt : >> Feel free to check if the size of the COM tags is correct or >> wrong by several magnitudes. > > I'm new to this topic and don't know exactly what a COM marker is > used for and how it should be. Could you please provide me some > links about it and how I can read this tags? Thank you The German Wikipedia is a good start, it contains all necessary information to understand this issue: https://de.wikipedia.org/wiki/JPEG_File_Interchange_Format >>The playing file does not contain COM tags;-) > > This means the COM tag is not necessary needed to play the > stream, but it will cause problems if the tag is wrong. Yes, in general, commentaries are not necessary to decode multimedia streams, broken parts of files can cause decoding errors. >>Which encoder are you using? > We are using a third party camera. I don't know about the > encoder they use. I meant: Which brand and model is the camera? Recognizing the encoder would make fixing your issue easier. Carl Eugen ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
> Feel free to check if the size of the COM tags is correct or wrong by several > magnitudes. I'm new to this topic and don't know exactly what a COM marker is used for and how it should be. Could you please provide me some links about it and how I can read this tags? Thank you >The playing file does not contain COM tags;-) This means the COM tag is not necessary needed to play the stream, but it will cause problems if the tag is wrong. >Which encoder are you using? We are using a third party camera. I don't know about the encoder they use. As soon as I understand the problem I will contact them. Thanks, Fabian ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
2018-09-18 8:44 GMT+02:00, Fabian Kurt : >> I tested the two streams you provided with vlc 3.0.4 and both >> behave exactly as with FFmpeg (which is generally expected). >> Did you test another version? > > But one of the files is working with FFplay, right? "Working" is not a strictly defined term I guess, but one video (the one with "notPlaying" in the title) plays with glitches, yes. I did not verify if the glitches are the encoder's fault (as I suspect) or if there is a bug in FFmpeg. > We tested with VLC 2.2.6. Which behaves exactly like FFplay here. >> More important though: >> But you did not comment on the main point of my reply: Why do >> you want to add a (possibly difficult) work-around for a broken >> encoder: Don't you control the encoder as well? Can't you fix it? > > So the problem with the COM marker is about the encoder. Are > you sure it's an encoder problem, on both streams? (The issue only exists for one stream.) Feel free to check if the size of the COM tags is correct or wrong by several magnitudes. > Why then does one play and the other not at FFplay? The playing file does not contain COM tags;-) > We can't change the encoder. Which encoder are you using? The main question here being: How can we detect the broken encoder? Carl Eugen ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
> I tested the two streams you provided with vlc 3.0.4 and both behave exactly > as with FFmpeg (which is generally expected). > Did you test another version? But one of the files is working with FFplay, right? We tested with VLC 2.2.6. > More important though: > But you did not comment on the main point of my reply: Why do you want to add > a (possibly difficult) work-around for a > broken encoder: Don't you control the encoder as well? Can't you fix it? So the problem with the COM marker is about the encoder. Are you sure it's an encoder problem, on both streams? Why then does one play and the other not at FFplay? We can't change the encoder. Thanks, Fabian ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
2018-09-17 13:46 GMT+02:00, Fabian Kurt : >> Do the streams really work with other players? > > Yes, we tested our application for several months with a built-in > VLC player and it worked well. > VLC needs several attempts to start playing the stream but > then it works fine. I tested the two streams you provided with vlc 3.0.4 and both behave exactly as with FFmpeg (which is generally expected). Did you test another version? More important though: But you did not comment on the main point of my reply: Why do you want to add a (possibly difficult) work-around for a broken encoder: Don't you control the encoder as well? Can't you fix it? Please remember not to top-post here, Carl Eugen ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
> Do the streams really work with other players? Yes, we tested our application for several months with a built-in VLC player and it worked well. VLC needs several attempts to start playing the stream but then it works fine. I noticed that FFplay has less delay than VLC. This was the reason to change. Fabian Kurt -Ursprüngliche Nachricht- Von: ffmpeg-user [mailto:ffmpeg-user-boun...@ffmpeg.org] Im Auftrag von Carl Eugen Hoyos Gesendet: Montag, 17. September 2018 12:54 An: FFmpeg user questions Betreff: Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates 2018-09-17 11:30 GMT+02:00, Fabian Kurt : > FFPlay is often not able to decode the stream. If we configure higher > bitrates of the camera output, FFplay is more often able to decode it > but not always. At lower bitrates <6Mbit/s it's mostly impossible to decode. > The main error occurring is: "No JPEG data found in image". This may not be the only problem but afaict the COM marker has a stored length that is always longer than the whole image. Not sure how this can be reliably detected in a mjpeg stream / FFmpeg does read the single images if you extract them. Do the streams really work with other players? Carl Eugen ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe". ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problems playing mjpeg stream at different bitrates
2018-09-17 11:30 GMT+02:00, Fabian Kurt : > FFPlay is often not able to decode the stream. If we configure higher > bitrates of the camera output, FFplay is more often able to decode it but > not always. At lower bitrates <6Mbit/s it's mostly impossible to decode. > The main error occurring is: "No JPEG data found in image". This may not be the only problem but afaict the COM marker has a stored length that is always longer than the whole image. Not sure how this can be reliably detected in a mjpeg stream / FFmpeg does read the single images if you extract them. Do the streams really work with other players? Carl Eugen ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
