Author Topic: The MLV format  (Read 1013 times)

Ilia3101

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The MLV format
« on: August 08, 2019, 12:09:00 AM »
Some time ago I remember hearing that the MLV format is getting extended with more features in Google summer of code for Apertus cine camera project. Did that ever happen?

A couple more questions:

1. Would developers consider adding new blocks to the official MLV format?

2. Where can I see most up to date version of mlv.h?
5D2, MLV App

Ilia3101

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Re: The MLV format
« Reply #1 on: August 16, 2019, 03:42:11 PM »
Ok never mind about the new blocks idea, raw_info has the matrix field I wanted. Though a "TEXT" block seems like a nice idea to me.

Anyway, I found mlv_structures.h on MLV post, and it is under LGPL (what I was hoping to find). However it does not contain raw_info structure, is that because raw_info is from CHDK and is full GPL? (I think I heard about this ages ago)

I am thinking there needs to be an mlv library (somthing like "libmlv"), that developers can use to add MLV support to their propreitary software. It would need to be licensed with LGPL or MIT, and written from scratch. But the GPL raw_info block is currently the main concern. Could it be done using byte offsets to access fields? - someone else calculates the offsets and communicates them to me.

I genuinely want to spread MLV as much as possible. No, I am not planning to sell any propreitary software with MLV support. I just want MLV to be a more widespread raw video format, I think it is perfect suited for that.

But first, I want to make a raw to MLV converter that converts other raw video formats or photo sequences to MLVs, so I can use MLV App with them. No licensing issues here as it will simply be GPL.


Anyone have any thought or advice about this?? About anything... The licensing issues, MLV for other cameras... bad or good ideas?
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Ilia3101

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Re: The MLV format
« Reply #2 on: August 18, 2019, 01:27:07 AM »
Ok let me condense the last verbal spaghetti post down to a couple of questions:

1. Is the MLV format suitable to use as a container for other raw video cameras' footage? (thinking of making a converter)
2. Would magic lantern community support the idea of a library (something like "libmlv") being created, with a license that does allow it to be used in proprietary software
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Danne

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Re: The MLV format
« Reply #3 on: August 18, 2019, 08:53:59 AM »
But first, I want to make a raw to MLV converter that converts other raw video formats or photo sequences to MLVs, so I can use MLV App with them.
How cool is that. I guess dng or tiff into mlv would be really convenient here. Or even jpg h264 maybe?

The library also seems like a good idea but I have little experience i this field. Maybe contact g3gg0 and a1ex directly too? Would be nice to see resolve and premiere implementing mlv support ;).

Ilia3101

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Re: The MLV format
« Reply #4 on: August 18, 2019, 05:17:44 PM »
How cool is that. I guess dng or tiff into mlv would be really convenient here. Or even jpg h264 maybe?
I saw in MLV headers that it can have h.264, but IDK if it has ever been tested or put to use (MLV App certainly doesn't handle h264 MLVs :D). DNG or cr2 would be easiest to convert to MLV though, especially if it is one of the already supported ML cameras, and masc found some nice libraries we could use.

The library also seems like a good idea but I have little experience i this field. Maybe contact g3gg0 and a1ex directly too?
Yeah I guess I should reach out to them. I'm just not sure about the licensing, I remember loads of something about Martin Herring's Footage app (Footage was completely closed, this library WILL be open source, but I would want it to be usable in proprietary software). As MLV headers are LGPL it should techincally be allowed... as long as raw_info can be dealt with, maybe using byte offsets

Would be nice to see resolve and premiere implementing mlv support ;).
It would be so satisfying if any of the industry giants were to implement MLV support. Maybe this is wishful thinking though :-\
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Ilia3101

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Re: The MLV format
« Reply #5 on: August 21, 2019, 05:45:03 PM »
Ok I found this https://github.com/apertus-open-source-cinema/opencine/blob/master/Source/OCcore/Image/mlv_structure_mod.h

It says it's LGPL, but contains the raw_info structure. Is that a mistake on their part?

Also I will forget the library idea for a bit, as I have heard from Apertus that their GSoC student will soon be finished with MLV format improvements... don't wanna make something already obsolete.
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g3gg0

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Re: The MLV format
« Reply #6 on: August 25, 2019, 07:51:26 PM »
back from holiday,

anything i could help with?

It says it's LGPL, but contains the raw_info structure. Is that a mistake on their part?

IIRC we aligned that that little part of the structure is fine to made LGPL to get the exchange format accepted.
only if even professional tools are allowed to use the structures, you can undercut commercial products with open source mindset ;)
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Ilia3101

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Re: The MLV format
« Reply #7 on: August 26, 2019, 02:49:27 PM »
back from holiday,

anything i could help with?

I'll probably have something soon :)

IIRC we aligned that that little part of the structure is fine to made LGPL to get the exchange format accepted.

Glad to hear

only if even professional tools are allowed to use the structures, you can undercut commercial products with open source mindset ;)

Yep, always fun to do that :D
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DeafEyeJedi

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The MLV format
« Reply #8 on: September 07, 2019, 08:59:09 AM »
Following this thread as it seems an important topic to keep up with. Fun facts. Thanks guys!
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extremelypoorfilmaker

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Re: The MLV format
« Reply #9 on: September 08, 2019, 06:44:24 PM »
Following :)