Ignore raw_frame_numbers when not playblasting to image format

[BigRoy]

Issue

When playblasting to a format that is not an image format with raw_frame_numbers = True Maya will give this warning:

# Warning: -movie flag cannot used with -rawFrameNumber option, using -image instead. # 

It will try to solve it and push on the "compression" settings to the image format, which in the majority of cases just fails to produce any valid output. From black frames or to the encoder not working and the playblast erroring out.

For example:

import maya.cmds as cmds
cmds.playblast(filename="C:/avi_format", rawFrameNumbers=True, frame=(1, 2, 3, 5, 9), viewer=False, format="avi", compression="MS-RLE")
# results in video with black frames

cmds.playblast(filename="C:/qt_format", rawFrameNumbers=True, frame=(1, 2, 3, 5, 9), viewer=False, format="qt", compression="Photo - JPEG")
# Error: Unable to initialize codec.
# Traceback (most recent call last):
#   File "<maya console>", line 3, in <module>
# RuntimeError: Unable to initialize codec. # 

Proposal

Instead of letting Maya fix it the wrong way I'd expect to have it just ignore raw frame numbers since it does not make sense out of the context of a sequence. So I'd opt for something like:

# Only image format supports raw frame numbers 
# so we ignore the state when calling it with a movie 
# format 
if format != "image" and raw_frame_numbers:
    log.warning("Capturing to image format with raw frame numbers is not supported. Ignoring raw frame numbers...")
    raw_frame_numbers = False

[mottosso]

Sounds good to me.