[FFmpeg-user] -preset veryfast produces smallest file, weird

[Reindl Harald]

Am 15.10.23 um 17:20 schrieb Ulf Zibis:
> 
> Am 15.10.23 um 16:52 schrieb Reindl Harald:
>>
>>
>> Am 15.10.23 um 16:43 schrieb Ulf Zibis:
>>>
>>> Am 15.10.23 um 15:43 schrieb Reindl Harald:
>>>>
>>>> if you prefer fast you don't care about quality
>>>>
>>>> in doubt quality needs space and find a compromise between size and 
>>>> space - you can't have both - and well, depending on the source 
>>>> material fast can be small and good enough in quality
>>> In my understanding quality also needs CPU time
>>
>> but with "veryfast" you statet "i do not care about quality" and 
>> losing details by not care about quality *can save* space - common sense
> 
> Then the info in the Wiki must be wrong

no

> With "veryfast" I stated to "not care about *space*", but with "-crf 23" 
> I always stated "care about same quality".

you statet "i don't care about anything but speed"
you didn't state more or less

is it really that hard to understand that depending on the input results 
differ *dramatically*? when you have a video with nearly no motion 
compression works far better

it all depends on the input and what quality loss is acceptable

and "verfyfast" simply don't care much about details - if the missing 
details make no visible difference for a specific input it saves space

with a different input the saving may be less but more visible

i really don't get why common sense won't lead to THE DIFFERNECE IS THE 
INPUT and what is acceptable as output

break the same down to zip: use it for a video or a html-file
guess what is more compressable

> Interestingly with "veryfast" I needed less space than with "medium" or 
> "veryslow"
and with different input it may look the opposite