Order dependency between video+audio

[maxnordlund]

I tried to download to separate streams and combine them using the -f bestaudio+bestvideo but it seams that the formats need to be in video+audio order. When I change the ordering it worked flawlessly.

I ran this:

$ youtube-dl ZJPVq71HCbg
[youtube] Confirming age
[youtube] ZJPVq71HCbg: Downloading webpage
[youtube] ZJPVq71HCbg: Downloading video info webpage
[youtube] ZJPVq71HCbg: Extracting video information
[youtube] ZJPVq71HCbg: Downloading DASH manifest
[download] Destination: Etho MindCrack SMP - Episode 187 - Elusive Farmers.f141.m4a
[download] 100% of 38.10MiB in 00:04
[download] Destination: Etho MindCrack SMP - Episode 187 - Elusive Farmers.f136.mp4
[download] 100% of 303.78MiB in 00:22
[ffmpeg] Merging formats into "Etho MindCrack SMP - Episode 187 - Elusive Farmers.m4a"
ERROR: Stream map '0:v:0' matches no streams.

With the this config file:

# Youtube Download config file
# Basic output format "Title.mp4"
--output "%(title)s.%(ext)s"
# Prefer 60 fps videos, but need seperate audio stream. The + combines them.
--format 299+bestaudio/303+bestaudio/298+bestaudio/302+bestaudio/bestaudio+bestvideo/best
--add-metadata
--prefer-ffmpeg

[jaimeMF]

That's intentional (see #3935 for reference), I have documented it. Thanks for the report.

For future reports, please post the output of youtube-dl --verbose URL, it makes debugging problems easier (for example we can quickly see if you are using an outdated version) and it also prints the options from the config file.

[maxnordlund]

Ok, that makes a lot of sense, thanks for the link. But I was hoping it would warn you earlier before it started to download, that the options are wrong if it is possible. Otherwise I hope that the error message could be more descriptive then Stream map '0:v:0' matches no streams. which doesn't tell me much unless you know about the ffmpeg flags from #3935.

[jaimeMF]

That's a good idea, I've added an error message that suggests changing the order. Thanks!