pygame: output to file?

[Terry Reedy]

On 4/16/2012 8:37 AM, superpollo wrote:
> alex23 ha scritto:
>> On Apr 16, 7:34 pm, superpollo <superpo... at tznvy.pbz> wrote:
>>> is there a way to convert the graphical output of a pygame application
>>> to a mpeg file or better an animated gif? i mean, not using an external
>>> capture program...
>>
>> There is, but it's probably not going to be as performant as using
>> something external:
>>
>> http://stackoverflow.com/questions/6087484/how-to-capture-pygame-screen
>
> but where in the code should i put the line:
>
> pygame.image.save(window, "screenshot.jpeg")
>
> ?

Somewhere in the loop that draws frames, perhaps just before or after 
flipping to the screen. Of course, number the frames.

framenum = 0 # somewhere, just once
# in loop
pygame.image.save(window, 'frame%05d' % framenum)
framenum += 1

5 digits for frames is just an example.
 >>> 'frame%05d.jpg' % 21
'frame00021.jpg'
 >>> 'frame{:0>5d}.jpg'.format(21)
'frame00021.jpg'

You might consider saving .bmp bitmaps, as mpeg compresses across frames 
as well as within frames. If you have sprites moving over a static 
background, only the changes need to be encoded.

-- 
Terry Jan Reedy