Cannot open hevc mp4 file that was saved by ffmpeg itself

[chao]

Summary of the bug:
How to reproduce:

% ffprobe no_start_code_hevc.mp4
ffmpeg n5.1
built on Ubuntu 20.04.4 LTS

I used command

ffmpeg -i "rtsp://XXXX" -an -vcodec copy no_start_code_hevc.mp4

to save a footage file from a security camera. The result mp4 file is invalid. ffprobe returns

[extract_extradata @ 0x560de7b1bb80] No start code is found.
test.mp4: Invalid data found when processing input

[Carl Eugen Hoyos]

Replying to chao:

ffmpeg -i "rtsp://XXXX" -an -vcodec copy no_start_code_hevc.mp4

This is missing complete, uncut console output but there is no guarantee that this command line produces a valid output file.

[chao]

Replying to Carl Eugen Hoyos:
I assume you mean the RTSP URL is cut out?
It's from a GeoVision security camera that's not owned by me.
Let me see whether I can share the RTPS URL here.

[Carl Eugen Hoyos]

Valid tickets contain a command line together with the complete, uncut console output, in this case of the command that created the invalid file.

[chao]

Well, I don't get the permission to publish the RTSP URL here.
I was hoping the mp4 file would be useful..

[Carl Eugen Hoyos]

We don’t care about the url, we want to see the command line you tested together with the console output.