[MPlayer-users] HD movies, aspect ratio, and scaling

[Tobia Conforto]

Hi
I have a couple of questions about a HD movie. I would like to better understand scaling issues.

The movie clip is WMV3 anamorphic 1440x1080 and my monitor has a 1440x900 resolution with square pixels. I'm using MPlayer OS X Extended rev12 (mplayer r29777)

The first issue is that ffwmv3 doesn't detect the aspect ratio of the movie clip. I guess that's a bug with FFMpeg.

So I go ahead and add the -aspect 16:9 option, and this is what happens:

Movie-Aspect is 1.78:1 - prescaling to correct movie aspect.
SwScaler: reducing / aligning filtersize 5 -> 4
SwScaler: reducing / aligning filtersize 5 -> 4
SwScaler: reducing / aligning filtersize 1 -> 1
SwScaler: reducing / aligning filtersize 5 -> 4
[swscaler @ 0x100ff60c0]BICUBIC scaler, from yuv420p to rgb24 using MMX2
[swscaler @ 0x100ff60c0]using 4-tap MMX scaler for horizontal luminance scaling
[swscaler @ 0x100ff60c0]using 4-tap MMX scaler for horizontal chrominance scaling
[swscaler @ 0x100ff60c0]using n-tap MMX scaler for vertical scaling (BGR)
[swscaler @ 0x100ff60c0]1440x1080 -> 1920x1080
VO: [corevideo] 1440x1080 => 1920x1080 Packed YUY2  [fs]

Why is it software-scaling the movie horizontally, up to 1920x1080? Can't it just play the 1440x1080 source in a 1440x810 window, using the hardware overlay? If that's not possible, wouldn't it be more efficient to down-scale vertically to 1440x810?

Tobia