Resize in 0.7.5.4742 and 4760

[Frisbee]

Hi,
Mediacoder 0.7.5.4742
1. While resizing video, the Height is always adjusted to nearest multiple of 16 even with Auto Adjust disabled. Custom Height adjustment cannot be done.

2. Is this how Auto Adjust works?

-One among Width or Height is adjusted,the other is obtained from user setting (Resize).
-Either PAR or DAR is specified by user (Keep or Set) and the other is taken same as that of original video.

3. The seeking in Time>Select still cannot be done.

Please help

[meRobs]

1. the various video Codecs ('formats') will generate only particular video frames sizes, which seem to be in multiples of 16, and most players, TV, etc also operate this way.

2. Resize, DAR, PAR, etc are explained in viewtopic.php?f=17&t=8197&start=0, and Cropping is related to these (see viewtopic.php?f=17&t=8188&start=0)

3. Time > Select allows Trimming/cutting, which is a function that works in only some builds of MediaCoder -- see: viewtopic.php?f=17&t=9611

All these and more are in the Tips & Guides page (link below).

[Frisbee]

The height being adjusted to multiple of 16 was absent in previous versions where a multiple of 2 closer to given height was selected and conversion was done without any problems with Xvid, H.264, MPEG4 etc.The adjustment to multiple of 16 causes much distortion in aspect ratio of low resolution videos with PAR=1. Also isn't that, codecs like Xvid and H.264 needs the height only to be a multiple of 2 though the PAR is set as 1 by default.

[Frisbee]

The height is adjusted to nearest a multiple of 16 by Mediacoder and it continues to be so in 0.7.5.4760. You an see it in the Avisynth options when in Expert user interface mode.
Really, it seems like it has nothing to do with the encoder or codec (most of them can have finer heights i.e. multiple of 2 or 4). I am talking about without Auto adjust.
Is there a specific purpose in setting the height this way? It really hinders the freedom in fine resizing especially at low resolutions.
Please give it a look...

[Jankes]

Same problem here, you're not alone.
This is just annoying when I don't want to resize and MC is forcing new resolution, yes, correct, Resize is disabled and resolution is still changing (eg. 854x480 to 856x480). This is wrong!
4732 (no 'devided by 8' rule) has become my favorite build, probably last, gotta feeling MC tries to make decisions for me.

[meRobs]

As you are discovering, the underlying utilities that MediaCoder relies on, such as FFmpeg, AviSynth, etc, all appear to have moved to the multiples of 8 rule.
This was probably done because codecs process data in micro-blocks of 8x8 pixels or 16x16.
From what I gather from a Google, if your frames are not exact multiples of 8, the codecs can still cope, but they do so inefficiently and either waste file size or add artefacts.

Most likely, MediaCoder will probably keep using recent versions of these utilities and, hence, this requirement of being a multiple of 8 will probably remain.
This will, of course, affect only very small frame sizes.
A distortion in aspect ratio would probably not be noticeable until the change exceeds about 8%, hence, a change of 4 is not a problem until frame dimensions drop below about 50 pixels.

If you use such small sizes, then, I suggest you move back to an earlier build, as is often stated in ths forum:

Should you update????
The newest version/build has all the latest features and some fixes. It is a "Beta" version that you can test.
If your current version/build is working, don't update unless you want to experiment.

[Frisbee]

Isn't it possible to resize the video as earlier and expand the frame to a 8 or 16 multiple height (with black bands; [b]Expand[/b] option in Mediacoder [b]Settings-Video Filters[/b]) so that the video won't get distorted and the resolution becomes codec friendly?

[meRobs]

Yes, you can 'Expand to Fit' as explained in viewtopic.php?f=17&t=8188&start=0
There are other Guides that may help as well (link below)

[Frisbee]

Hi,
Expand to fit doesn't seem to work when the source video has non standard aspect ratios. Error 15 occurs when doing this. The console shows something like Full DR not possible: Working with slices (Sorry I am unable to post full details now)
It works fine with a 1080p video.
Source video:
Xvid;mp3;AVI
W: 656 H: 264 (Aspect ratio: 2.48:1)

Output:
Xvid;AAC;3GP (PAR: 1:1)
W:176 H: 144

I tried Expand to fit so as to fit the video into the 176 by 144 without distortion in picture aspect ratio by allowing black bands above and below.
Please help

[meRobs]

I doubt whether the 'Expand to Fit' setting caused the probelm, per se.

In build 4777, I took a widescreen file and:

I used the x264/MP4 settings in the far right column of the Encoding guide (listed among the Tips & Guides, link below).
Then, changed, Resize to 176x144, Aspect Ratio to Set PAR = 1:1 and Crop = Expand to Fit.
That worked.
Then, I changed, Container to 3GP, all else the same, and that worked!