Crop basics

[sargan]

Need to crop off black borders on some video files.

Open a video file (a 960x720 file)
Add null transform filter [OK]
Click on 'cropping button'
Set the X, Y co-ordinates [OK] (As example 40 off X and 20 off Y)
click [OK] to close filters window

right hand window shows correctly cropped image.

video > full processing
video > select compression > GV Lossless
File save as AVI 'cropped.avi'

If I now- without closing & reopening VD, click 'play' in VD the right hand window plays at reduced crop size - so looks successful.

However if I go to the 'cropped.avi' file, it is exactly the same size at 960x720 ?

If I open cropped.avi file in VD ... it once again opens with the borders .. i.e unchanged

I expected the file to now be reduced in size equivalent to the crop ........ have I done something wrong, or am I misunderstanding the command.

[raffriff42]

What color depth settings did you have? (not sure, but v210 might bypass VD's filters)

[sargan]

What color depth settings did you have? (not sure, but v210 might bypass VD's filters)

The intermediate encoding was in VD using Grass Valley Lossless, there are no configuration options for this, used as is.
The fourcc code is cllc (not V210)
Bit depth = 8

As a test I just run it again this time saved as uncompressed .. and the files is now correctly sized .... hmmmm

Does that mean I can't use GV Lossless when resizing ? or is there a way to force it to use the filter.
I'm a beginner at this stuff so confusing me somewhat.

[raffriff42]

I compressed an AviSynth script (YV12) with cropping & GV lossless as per post #1, and it worked fine for me.

[sargan]

Found the difference .......... my sequence was slightly different to my description ...

As input file was GV Lossless was using Fast recompress > GV Lossless

If I use compression > GV Lossless then the output file is cropped to size expected

If I use fast recompress > GV Lossless it fails

Not sure if this is expected behaviour, but at least I have a way forward.

[StainlessS]

To change video in any way you need to use Full Processing mode, not fast recompress, so that is expected the behaviour.

[sargan]

To change video in any way you need to use Full Processing mode, not fast recompress, so that is expected the behaviour.

OK my misunderstanding thought if input was Lossless and output was the same I could use fast recompress.

When do (can) you use fast recompress?

[raffriff42]

> When do (can) you use fast recompress?
When you aren't doing filtering. The only thing you can do is timeline edits.

VirtualDub help - Processing: Filtering videoThe video processing mode must be set to Full processing mode for the video filter system to be enabled. If the video processing mode is set to anything else, the Filters... menu option is grayed and the video filter chain is disabled.

[sargan]

Thankyou for explanation

[StainlessS]

Thank you raffriff for you clarification, I should have made myself more clear.