[Matroska-devel] mkv conversion

[Christian HJ Wiesner]

Hi Dave,

in this case, i can just encourage you to have a look at the great VLC 
player from http://www.videolan.org . It is opensource and and GPL and 
can be modified by you according to the laws of the GPL, and as long as 
you will distribute it as freeware and make your modifications available 
under the GPL to others, you will be fine. Of course, you may not 
release it as payware in this form, but i recommend to replace the VLC 
components for this version with your own code later, after having 
achieved some attention with your freeware version already in an 
existing user base.

The integrated VLC conversion tool is almost perfect, it can read most 
files and output high quality H.264, XviD (MPEG 4) and MPEG2 video. It 
just needed a much better user interface and urgently a cropping and 
resizing filter so that people are able to alter the pixel resolution in 
the final encoding, allowing e.g. to downsize a HD encoding into normal 
DVD resolution. What is also needed is a channel selector, so that 
people can choose the right audio track in multi-language files. VLC 
player is programmed in C AFAIK, i hope this is fine for you ?

Alternatively, if you program your own tool from scratch, you might have 
a look at Haali's free MKV parser, released under the BSD license. You 
can find it here : http://haali.cs.msu.ru/mkv/MatroskaParser.zip . 
However, you will need the same for MPE2 decoder, h.264 decoder, MP3 
decoder, MPEG4 decoder, MPEG 2 ENcoder, etc. Honestly, i dont think you 
will be able to make all of this by yourself, especially with respect 
for the expected encoding quality of your encoders. It does require 
quite a lot of know how to program a high quality encoder, and it will 
take you years until you have that, and manage to make a single good 
encoder by yourself.

Regards

Christian

Dave schrieb:
> Hello Christian,
> At this time I am looking at a totally free conversion tool. I am 
> looking to include .mkv, .vob, mpeg2, ipod, hd,  to start off.
> Some venders may not let me merely "use" their library without a fee, 
> but my first task is to put together a useful tool using free codecs 
> and libraries and to design a pleasing interface. Packaging is so 
> important to a user. I use a win XP pro system with 3 ghz P4 CPU plus 
> ATI 1650 pro video with a 1 gb of ram, plus I have a vista ultimate 
> system having 2 gb of ram with a 6850 Core 2 Duo chipset plus the 
> nividia 8800 p-cie card.
> The future may allow a commercial application of my tool and I will 
> work toward that goal.
>
> Thank you,
> Dave
>
>
> with ----- Original Message ----- From: "Christian HJ Wiesner" 
> <chris at matroska.org>
> To: "Discussion about the current and future development of Matroska" 
> <matroska-devel at lists.matroska.org>; <cottle at stx.rr.com>
> Sent: Thursday, December 27, 2007 5:14 AM
> Subject: Re: [Matroska-devel] mkv conversion
>
>
>>
>> Hi Dave,
>>
>> we are actually very interested in adding more MKV file conversion 
>> tools to our homepage, because this is one of the most asked 
>> questions from our users. Conversion into AVI files is nonsense, and 
>> should not be attempted. AVI is too old and not powerful enough to 
>> hold the same content as MKV, that was the main reason for us to 
>> start the MKV project in the first place.
>>
>> However, conversion of MKV files - especially hi-res HDTV files 
>> containing h.264 (AVC) encoding, requiring strong CPUs for realtime 
>> playback - into high quality DVDs is one of the most asked tasks, and 
>> also well possible.
>>
>> Before we can help you, we need more information :
>>
>> - Is your tool freeware, opensource, or a commercial project ?
>>
>> - what output formats will your tool support ?
>>
>> - did you consider to add MKV output to your tool also ?
>>
>> - what licenses do you expect from those libs ? More specifically, 
>> will they be part of a commercial project ?
>>
>> As a sidenote, the great Videolan player from http://www.videolan.org 
>> can open and play most MKV files out there (besides those with 
>> Realvideo RV9/RV10 and On 2 VP 6/7 video compression), and can also 
>> convert them into MPEG2 already. Unfortunately, it has no video 
>> resizing filter, and also no stream selector (e.g. to select the 
>> right audio stream/language from a multi-language MKV file).
>>
>> Another alternative is to do the same as DVD Santa is doing, i.e. to 
>> use a DirectShow based input plugin. Doing so, your tool will be able 
>> to convert all files that can play in Windows Mediaplayer and other 
>> DShow based players. The suitable MKV demuxer filters are available 
>> on http://haali.cs.msu.ru/mkv/. The same homepage will also hold the 
>> most comprehensive list of supported video and audio codecs in MKV 
>> files : http://haali.cs.msu.ru/mkv/codecs.pdf . Bear in mind, MKV is 
>> currently the most powerful container existing, a MKV file can 
>> basically hold everything under the sun ;-) .....
>>
>> Best Regards and Happy New Year
>>
>> Christian
>>
>>
>> Dave schrieb:
>>> I am a programmer wanting to develop a conversion for the MKV 
>>> extension to change to orher video formats. I am intested in what 
>>> tools or libraries you have to help me accomplish this. I have seen 
>>> other programs available that do this.
>>> Thank you,Dave 
>
>