rtsp_transport ignored in avformat producer about mlt

[ddennedy]

MLT uses libavformat for this. It all depends on who provided your libavformat, its version, and how it was built. Also, you may need to supply parameters on the URL query string instead of on the producer. Also none of MLT maintainers have convenient access to RTSP let alone a TCP variant of it to provide much assistance or debugging. If you want to get anywhere with this you should provide info on how to create such a stream and exactly how you are trying to read it with melt. If it is not convenient or obvious, I doubt anyone wants to address this bug report.

[ddennedy]

Some tips:
Run melt -query producer=avformat to see if that libavformat parameter exists in your version.

Try to preface the URL with 'avformat-novalidate'. By default, MLT avformat producer opens the resource upon construction of the object to verify it can actually be used and gather basic info such as duration, default stream indexes, and seekable. If it is not seekable, then the resource is kept open, which likely means MLT properties after construction might not have any effect. "avformat-novalidate" skips that step, and you ought to be able to then set additional MLT properties needed prior to the actual stream open.

[matiaspl]

The parameter existed in my version and unfortunately avformat-novalidate tended to segfault with the versions I used. Now I'm experimenting with main git branch and haven't tried yet. While I have your attention - is there any way to make melt+avcodec send frames as soon as they are processed? I'm sending the data (sample clip) to a rtmp server and the data arrives only after the whole clip is processed or the process is interrupted by pressing 'q' or 'ctrl-c'.

Edit: the latter issue doesn't show up in the latest mlt/melt version.

[matiaspl]

As you said it's all in the ffmpeg version. To sum up what I've learned - with the latest git version some streaming inputs work (i.e. UDP, HTTP), some don't (RTMP) and I couldn't find any key to what doesn't work and why. And avformat-novalidate doesn't work with with UDP at all. All the streams I tested work fine with the standalone ffmpeg executable built alongside with melt.

[ddennedy]

No one is going to fix this for you. Submit patches, but this is a horrible bug report as written; so, I am closing it. For example, what is an "rtmp camera" and what does it have to do with RTSP? It is not even clear if this is about streaming input or output.