[FFmpeg-user] ffmpeg makes some sources darker

[Andy Furniss]

Jim Worrall wrote:
>
>> On 2016 Jan 6, at 4:04 AM, Andy Furniss <adf.lists at gmail.com>
>> wrote: I guess superfast hides the gain of the first pass. I am not
>> sure I would want to encode with it using 3M ABR - which is quite
>> low, but then libx265 is quite slow.
>
> Normally I use ‘medium', or now ‘slow' because I’ve got my NAS set
> up with ffmpeg and just let it crank there in its own sweet time.
>
> I started with testing a range of bitrates at medium 2-pass from a
> bluray source.  At least looking at the pngs, I found I couldn’t
> really see any clear improvement above 2 Mb/sec, so I chose 3.  I
> can’t distinguish it from the source (except for the light/dark
> business in some cases). Do you think the ‘png test’ doesn’t give a
> good comparison?

Fair enough. I can see that 3M was enough with default for the sample
you posted, but not much happens in that.

I was just thinking that 3M + superfast could be a bit low for high
action scenes with flying cameras etc. As you are not using superfast
anyway that concern does not apply.