Correcting aspect ratio in an mp4

[tpapictures]

Is there some software that can handle converting the aspect ratio of a video file easily without doing anything further to the original video file? Just a 1.85:1 video I need converted to 2.35:1.

Thanks!

[manono]

Was it originally 2.35:1 but at 1.85:1 it's playing 'squeezed' with everyone too tall and thin? Or, at 1:85:1 the aspect ratio is okay and you want to cut from the top and bottom to make it 2.35:1 and still keep the aspect ratio correct? Or you want to change it to 2.35:1 by 'stretching' it so everyone looks short and fat?

Also, give the kind of video it is, maybe a MediaInfo text readout. What might work for one might not work for another to just change the aspect ratio without reencoding. Or are you okay to reencode the whole thing?

[tpapictures]

Or are you okay to reencode the whole thing?

I prefer to reencode the whole thing. I don't want to have to do tweaks later. I watch on a rpi2 running Kodi and I prefer to have the video fixed correctly.
It's currently 1.85:1 because the original 2.35:1 was captured incorrectly. I need to convert that 1.85 to 2.35 and would rather do it permanently.

[manono]

So, it's wrong now and stretching it out to some 2.35:1 resolution will correct the aspect ratio?

If so, then you might check out Vidcoder. Here's a thorough tutorial:

http://www.digital-digest.com/articles/VidCoder_Tutorial_page1.html

On the second page is a picture which seems to show you being able to set the resolution. I don't use it myself, so maybe someone will come along and confirm (or deny), it can do what you want.

[jagabo]

Why don't you just set the AR in the header? There will be no reencoding so no loss of quality. RPi will play that with the specified AR.

[tpapictures]

Why don't you just set the AR in the header? There will be no reencoding so no loss of quality. RPi will play that with the specified AR.

That sounds worth a try. How do I edit the header? I mean is there a particular application that does it flawlessly?

[jagabo]

Why don't you just set the AR in the header? There will be no reencoding so no loss of quality. RPi will play that with the specified AR.

That sounds worth a try. How do I edit the header? I mean is there a particular application that does it flawlessly?

I usually do it by demuxing the audio and video (and other) tracks, then remuxing them with Mp4Muxer.
https://www.videohelp.com/software/MP4Muxer

[tpapictures]

I just looked at one video (that is correct) in Media Info and noticed that the difference is not in res but rather in pixel ratio.
The correct one says:
Bits/(Pixel*Frame) : 0.139

The one that is squished and I need to correct says:
Bits/(Pixel*Frame) : 0.100

So, that is what I need to fix.

[jagabo]

No, that 's very rough measurement of video quality. It has nothing to do with the aspect ratio. What you want to look for in MediaInfo is the Display Aspect Ratio.

With MP4Muxer: the actual frame size of this video is 854x480 (~1.78:1) . But the header flags are telling the player to play it at 1128x480, or an aspect ratio of 2.35:1:


[Attachment 40437 - Click to enlarge]

[tpapictures]

What you want to look for in MediaInfo is the Display Aspect Ratio.

Ok, I figured out the problem. The one I was seeing as "correct" is encoded with black bars as part of the image. THAT's why it says 16:9 even though the video content is 2.35:1. A watermark made me aware of that.
In the "incorrect" one, there are no bars encoded into the full frame so it's 2.35 playing out at 16:9. So that's what I need to fix.

[jagabo]

MediaInfo and media players don't know you aren't interested in the black borders.

[tpapictures]

Ok. In case anyone ever reads this...
I used My Mp4box to demux with the embedded subtitles. Could have used anything else but in this case the subs were not extractable any other way. Then I joined everything in mkvmerge where I properly labelled the audio track and subs to english and set the ratio at 2.35:1.

[poisondeathray]

You shouldn't have to do the 1st step of demuxing first. mkvmerge/ mkvtoolnix should be able to import the mp4

[tpapictures]

You shouldn't have to do the 1st step of demuxing first. mkvmerge/ mkvtoolnix should be able to import the mp4

I had to, like I said, because mkvmerge wouldn't see this particular mp4 video's subtitles. MyMP4box is the only thing that would see them and extract them to an srt file.

[poisondeathray]

Interesting that mkvmerge couldn't "see" the subs. Do you have a small sample you could upload ?

Alternatively, I think everything could have been set with mp4box if you wanted mp4 container. But it's slightly different in that you set the track PAR (pixel aspect ratio), not the DAR (display aspect ratio) of the video. You can assign language to tracks as well

[tpapictures]

Interesting that mkvmerge couldn't "see" the subs. Do you have a small sample you could upload ?

Correction mkvmerge-GUI 4.8.0 couldn't. Just tried mkvtoolnix 9.8.0 and it DID see them. I went with mymp4box because I saw several other people having the same problem with heavily embedded subs.

Alternatively, I think everything could have been set with mp4box if you wanted mp4 container. But it's slightly different in that you set the track PAR (pixel aspect ratio), not the DAR (display aspect ratio) of the video. You can assign language to tracks as well

I'm gonna play with it anyway, just to see what it does. Thanks.

With all these applications, and both 32 and 64 bit, I wish there was some way to have a GUI that could act as a hub for all these apps with explanations for what they all do to use them later. I invariably end up digging through all of them one by one later to see which one did this or that and wasting tons of time. Anyone know of an application like that where you can make a simple hub of application links with descriptions?

[poisondeathray]

With all these applications, and both 32 and 64 bit, I wish there was some way to have a GUI that could act as a hub for all these apps with explanations for what they all do to use them later. I invariably end up digging through all of them one by one later to see which one did this or that and wasting tons of time. Anyone know of an application like that where you can make a simple hub of application links with descriptions?

I don't think so.

One big problem is there are bunch of different tools for different formats, a bunch of different developers and it's difficult to maintain. When there are some big syntax / API changes, it breaks compatibility, the GUI needs to be updated

Another problem is it's difficult to have a GUI that includes everything. There are many commands that might not be included because they might not be used that often , and only accessible by commandline . And if you included everything it would be unusable cluttered GUI - so only the common tasks are typically included

[tpapictures]

I don't think so.

Right, but I'm just saying a simple window with a list of clickable launchers to go to all these different applications. There is an application called PS2tools which is all tools for various tasks on PS2. Memory card tools, etc. And all it does very simply and with no fuss is give you a simple GUI for clicking the different tools. It's like a toolkit, I guess. And then you just have buttons that act as launchers for different tools. Something like that with all these media tools with a little editable blurb for each one would be fantastic.