Issue transcoding H.265 to H.264 stream with FFMPEG

I’m having an issue trying to do some tests restreaming an H.265 stream to H.264 as follows:

• I use a MP4 file as video source, then I use VLC to stream it with H.265 codec as follows:

1. I go to media -> stream menu, then select a file and stream:

2. The second step allows me to add a destination for the stream, I chose HTTP:

3. The next step allows me to select a profile, I select Video – H.265 + MP3 (MP4) profile leaving the Activate Transcoding option:

• Previous steps allow me to stream the video file, I can open another instance of VLC and open the URL of the created stream (http://localhost:8080/test) and it is able to playback the stream. Moreover, if I go to Tools -> Codec Info menu I see that the playback indeed uses H.265 codec.

• Then I try to use FFMPEG library to take that input stream and transcode to two separate stream, one H.264 for a copy of the video and another an opus audio output with the following command:

ffmpeg -i http://localhost:8080/test -c:v libx264 -bsf:v h264_mp4toannexb -b:v 2M -profile:v baseline -pix_fmt yuv420p -x264-params keyint=120 -max_delay 0 -bf 0 -listen 1 -f h264 unix:/tmp/myvideo.sock -c:a libopus -page_duration 20000 -vn -listen 1 -f opus unix:/tmp/myaudio.sock

But I get the following error:

If I try RTSP instead of HTTP it works but the stream is awful, I can barely see some frames on the receiver and the video usually freezes or just shows black.

I’m using Ubuntu with VLC 3.0.18 and FFMPEG 4.4.2.

I have specific requirements to handle the live streams, I cannot just convert and save to a new container (MP4 file) the transcoded video, I require a source streaming H.265 and transcode the stream to be injected into a WebRTC server (requiring H.264 as input).

Any help/suggestion is much appreciated in advance!