ITVX producing washed out blacks

Ninko

Hi,
Has anyone noticed that when downloading anything from ITVX, blacks seem washed out, looking more grey then black? After looking at the properties of the files, it reports using full RGB colors, shouldn't it be using limited colour space?

Thanks

whitesnake

Hi,
Has anyone noticed that when downloading anything from ITVX, blacks seem washed out, looking more grey then black? After looking at the properties of the files, it reports using full RGB colors, shouldn't it be using limited colour space?

Thanks
Ninko

I'm more suprised you are actually downloading from ITVX because nobody else can

Germania

downloading from ITVX ... nobody else can
whitesnake

That's definitely wrong - see my postings in ITVX still not working

@Ninko
ITVx really doesn't always have the best quality, but I don't use it that often.
Can you give a concrete example?

But I'm sure that SF won't make anything worse
(if not using old version with re-encoding)

Ninko

@Germania Try downloading an episode of, The 100, and try playing it on a standard TV and your see how the picture looks washed out, the blacks look like greys.
And if you check with MediaInfo your see that colorspace is set to Full, when it's meant to be Limited, this is the problem, standard TV is normally set to Limited colorspace.

Germania

I dl "The 100.s01e01" 720p AVC from ITVx, amazon de and netflix us

itvx: yuvj420p(pc, bt709, progressive) | Color range : Full
amazon: yuv420p(tv, bt709, progressive) | Color range : Limited
netflix: yuv420p(progressive) | Color range ?

(itv manually dl identical = unchanged by SF)

I don't know much about it - does anything change on the TV if you change it with ffmpeg
ffmpeg -color_range tv (Colorspace support in FFmpeg)

Ninko

So ITVX is actually providing full colour range?

It's my understanding that's not standard, full colour range is generally used on computer monitors and limited is used for TV, hence why many TVs can't display full colour correctly.

Could you see how it looks washed out on a TV, blacks looking grey?

Obviously if ITVX is providing that themselves I'm not sure if there is anything SF can do about it, unless they can change the colour range to limited during encoding? I didn't actually know you could change colour space using ffmpeg.

october262

So ITVX is actually providing full colour range?

It's my understanding that's not standard, full colour range is generally used on computer monitors and limited is used for TV, hence why many TVs can't display full colour correctly.

Could you see how it looks washed out on a TV, blacks looking grey?

Obviously if ITVX is providing that themselves I'm not sure if there is anything SF can do about it, unless they can change the colour range to limited during encoding? I didn't actually know you could change colour space using ffmpeg.
Ninko

see here on the colorspace support - https://trac.ffmpeg.org/wiki/colorspace

Ninko

Thanks @october262 I've already read that, way over my head . I've not used ffmpeg very much.

Germania

> So ITVX is actually providing full colour range?

I checked "Sorry For Your Loss" and "Trigger Point" - both have Color Range: Full

> It's my understanding that's not standard

99% of my YUV videos is limited color range

I play on PC and TV is Dual-Monitor - my differences can fixed with contrast + brightness

To change color range i used:
ffmpeg -i The_100_S01E01_Pilot.mp4 -c copy -color_range tv The_100_S01E01_Pilot_4tv.mp4

Ninko

[QUOTE=To change color range i used:
ffmpeg -i The_100_S01E01_Pilot.mp4 -c copy -color_range tv The_100_S01E01_Pilot_4tv.mp4[/QUOTE]

Does that actually convert the colour range, i.e. 1=black becomes 16=black or is it just changing the colour range tag, essentially still looking washed out?
Thanks

Germania

I am afraid it's only "changing the colour range tag"

To convert i think it must re-encoded - see: FFmpeg: how to flag an H.264 video as in full color range?

test:

ffmpeg -i The_100_S01E01_Pilot.mp4 -c:v copy -bsf:v h264_metadata=video_full_range_flag=0 -color_range tv The_100_S01E01_Pilot_4tv+.mp4

Ninko

I'll try it at some point, thanks, I don't mind re-encoding, but that's why I was wondering if SF should do this automatically as part of its encoding phase.

Germania

My last code change also pix_fmt from yuvj420p [0-255] to yuv420p [16-239]

> I was wondering if SF should do this automatically as part of its encoding phase.

SF leaves the videos unchanged and I think that makes sense

Ninko

Have you confirmed that code works then?

As for SF, normally I would agree, but full colour range, is far from standard, I'm not even sure why ITVX themselves are using it, I've not come across this problem with any other provider currently.

Germania

> Have you confirmed that code works then?

ffprobe confirmed me (my converted video)

Ninko

Could you give me brief instructions on how to use ffmpeg to execute the code, I've never actually just used core ffmpeg before?

Thanks

Germania

What am I supposed to explain?

The easiest way is to copy ffmpeg.exe (here in bin) into the path (e.g. in Windows) or put it in the video directory

Opens the command line (in powershell use command: cmd) and changes to the directory where the video is located, e.g.

cd "%USERPROFILE%\Documents\DVDFab\StreamFab\Output\The 100\S01"

and use the code from post #11 (after adjust the filenames - for spaces i add quotation marks):

ffmpeg -i "The_100_S01E01_Pilot.mp4" -c:v copy -bsf:v h264_metadata=video_full_range_flag=0 -color_range tv "The_100_S01E01_Pilot_4tv+.mp4"

Ninko

Ok I'll try it, like I say, never used it before.

Thanks