Hi,

I am working here on a 40 min long documentary and i need to get it from full hd to the best .vob quality, since the authoring is going to be printed in many copies!
Very excited about that, though i have not been able to get a proper quality for it...
Ive tried

NTSC 16:9 CBR Preset:
properties=dv_ntsc_wide/DVD mlt_profile=dv_ntsc_wide pass=%passes

And NTSC 16:9 in quality 3 (the best..):
properties=dv_ntsc_wide/DVD mlt_profile=dv_ntsc_wide qscale=%quality ab=%audiobitrate+'k'

Both give a very poor output... kind of blurry. So anyway a friend of mine offered to help me with his windows thing...
but i think its not the idea! the whole proyect was made in kdenlive and its made for the government, so i think its a good start for me to stand up for open source...
so, any suggestions on parameters? perhaps create a new profile??
Any suggestion is very welcome!

Ill leave here the poster ive made for the premiere of the documentary ...thanks in advance!

Hello!

I had the same problem but I found the answer with some information in your question.

I had been approaching the problem by trying to use a rendering profile with 'properties=MPEG-2' and attempting to specify the video size and aspect ratio to be DVD compliant. This never worked because I could only resize the video or specify the aspect ratio, but never both.

In reading your question I learned about property 'dv_ntsc_wide/DVD' and MLT profile 'dv_ntsc_wide' which I had never seen before. Using the information you posted, I was able to create a slightly better video output by using a custom rendering profile containing:

properties=dv_ntsc_wide/DVD mlt_profile=dv_ntsc_wide qscale=%quality ab=%audiobitrate+'k'

and specifying '1' for the quality. The quality settings in the drop-down list in the profile are just suggestions, you can select other numbers. 1 seems to be the best (I did try 0 and -1 but the default quality setting must have overridden these invalid numbers).

I tried specifying a video bitrate using vb=8000k but that didn't make any difference in quality. I was able to determine that the mlt_profile will only work with 'constant quality' and not a fixed bitrate.

Doing some more searching on 'mlt_profile=dv_ntsc_wide', I was able to find how to specify the parameters for constant quality. Doing this, you can specify a target bitrate and a minimum bitrate so that your overall video quality is better than the default settings in mlt_profile=dv_ntsc_wide.

You will want to create a new rendering profile containing this:

properties=dv_ntsc_wide/DVD f=dvd vcodec=mpeg2video acodec=ac3 s=720x480 b=8000k maxrate=9000k minrate=6000k bufsize=1835008 packetsize=2048 muxrate=10080000 ab=192k ar=48000 me_range=63 trellis=1 g=18 mlt_profile=dv_ntsc_wide pass=2

There is some redundancy in here. For example, you don't need to specify the video size (s=720x480) because that's the default but I left everything in so it can be seen and understood. I've also found that the order of the parameters makes a difference. The 'mlt_profile=dv_ntsc_wide' parameter needs to be at the end of the list else the aspect ratio is 3:2 instead of 16:9. Maybe someone who reads this will know why.

I don't know how much you know about constant quality MPG2 so I'll explain a couple of the important parameters you might want to modify.

b=8000k is the target video bitrate. 8000k is high quality and probably the highest you should try.
minrate=6000k is the minimum video bitrate. Keeping this high will help keep video quality. If you have a problem keeping the file size small enough to fit on a DVD, lowering this might help. I think the default setting for this is 0.

All of the parameters are defined at http://www.mltframework.org/bin/view/ML ... erAvformat

You can also substitute 'properties=dv_ntsc_wide/DVD' with 'properties=MPEG-2'. Both will work and produce valid DVD-compliant output but the file size is slightly smaller when using 'properties=MPEG-2'. I don't know if there is difference in quality.

Thanks for posting your question because it helped me find my answer. Let me know how this turns out for you!