[MEncoder-users] Convert to PSP compatible MP4： Rescaling

[James Hastings-Trew]

Shuang Wu wrote:
> *James Hastings-Trew* wrote:
>   
>> Unless I am horribly wrong here (under the influence of cold medicine)
>> you'll need to actually calculate the scale yourself rather than rely on
>> the -10:272 trick. Then you'll need to put a dsize command in your
>> filter chain to set the PAR.
>>
>> -vf pullup,softskip,scale=xxx:yyy,dsize=xxx:yyy,harddup,unsharp=l3×3:0.7
>>
>> That should fix that problem for you... but that might be the codiene
>> talking.
>>
>>
>>   
>>     
> Thanks for your advise. But it's still not work...
>
> And I found if I specify
>
> -vf pullup,softskip,scale=xxx:yyy,dsize=xxx:yyy,harddup,unsharp=l3×3:0.7
>
> where xxx is more than 400 pixels, e.g. 416:272, the recaling would be
> done without any problem,
> but otherwise, it would definately fail, such as 320:240. I also tried
>
> dsize=xxx:yyy:2
>
> and the '-aspect' instruction
>
> -aspect xxx:yyy
>
> It was not work either.
>   
The PSP is definitely weird when it comes to the format of the video
it's going to be happy with. From my information, max width is 480, max
height is 272, max video bitrate is 768, and max audio bit rate is 128
aac. I've encoded lots of videos to PSP format, and mine have always
worked aspect ratio - wise. Looking through my code, I found that I was
also expanding the video to make it the right size:

-vf
pullup,softskip,scale=xxx:yyy,harddup,unsharp=l3×3:0.7,expand=480:272,dsize=480:272

That'll sort of letterbox or pillarbox the video and it'll always
display on the PSP at the right aspect ratio. Maybe that'll work for you.