[FFmpeg-devel] Vertical bands with RT21 (Intel Real Time Video 2.1) codec

[Mats Peterson]

On 12/19/2015 04:03 AM, Mats Peterson wrote:
> On 12/19/2015 04:01 AM, Mats Peterson wrote:
>> On 12/18/2015 01:22 PM, Mats Peterson wrote:
>>> On 12/18/2015 05:32 AM, Mats Peterson wrote:
>>>> On 12/18/2015 05:12 AM, Mats Peterson wrote:
>>>>> On 12/18/2015 04:13 AM, Mats Peterson wrote:
>>>>>> Samples:
>>>>>> https://drive.google.com/open?id=0B3_pEBoLs0faei1Sd1h6SG11QlE
>>>>>>
>>>>>> Mats
>>>>>>
>>>>>
>>>>> The clips are sample clips from Video for Windows, in case anyone
>>>>> wonders. I haven't created them myself.
>>>>>
>>>>> Mats
>>>>>
>>>>
>>>> The output is generally washed-out, as well, apart from the bands.
>>>>
>>>> Mats
>>>>
>>>
>>> I noticed this issue has been discussed as far back as in 2005 (see
>>> http://sourceforge.net/p/ffmpeg/bugs/310/), but using the slightly
>>> different terms "ghosting and shadow effects". In any case, it obviously
>>> still hasn't been fixed.
>>>
>>> Mats
>>>
>>
>> Sorry, Paul, I accidentally removed your reply. Anyway, as an answer to
>> your question regarding whether I know software that plays/decodes the
>> videos correctly, yes, the IR21 codec in Windows 3.1. Support for RT21
>> was unfortunately dropped in later versions of Windows, as far as I
>> know. And thanks, Piotr Bandursky, for providing the raw output from
>> ir21.dll. That's the way it should look.
>>
>> Mats
>>
>
> Bandurski, sorry.
>

I have (once again) checked the videos in dosbox/windows 3.1, and there 
is still a tendency of vertical bands, but that seems to be inherent to 
the codec. In any case it is to a much lesser degree than in the output 
from FFmpeg.

Mats

-- 
Mats Peterson
http://matsp888.no-ip.org/~mats/