this might have been asked so often but searching the forum doesnt give me any results:

What would be the best high quality format to render out a film to make a projection via laptop and a high quality beamer?

I m a little confused with the new rendering options ins 15.13. so i want to hear your opinions..

now i try .h264 and put the slider to high quality. but the file is still pretty small for my understanding (approx. 4gb on 60minutes), what options would you chose to get a high quality rendering , which is still small enough to be able to be played ?

Does the resulting video file when playing satisfy your quality expectation? Then go for it and never worry about the file size not exactly what you expect.

I use extensively an HDMI standalone recording device. It produces small H.264 video in mp4 containers at 30fps full HD resolution. The quality is more than satisfying, yet the files are incredible small. This recording device is originally aimed at gamers, which are probably a picky bunch. Anyway the resulting video is fine. So I don't mind.

4gb for an hour of 1080 @ 30 seems quite reasonable to me. crf encoding which is what kdenlive uses by default and is the default, recommended encoding method of x264 is very good at producing videos at arbitrary quality levels.

thanks for your answers!! finally the encoding is done after a view hours and the result looks pretty good on my laptop.. i ll see how well it performs on a big screen... but it looks pretty good. i was just confused by the new rendering dialog a bit, as i remember before when i set the rendering on h264 to the highest quality (not lossless..) i got much bigger files (that sometimes where also too big to play back properly...)

There is a lot of variety in rendering devices which you don't have much control over. For instance, different media players on PCs, media players on tablets also tend to give different results, albeit not as extreme as on PCs as long as they use the device hardware rendering support. Then, TV displays give even more varying playback results.

Just try a few to get a feeling on what can't be controlled...

For instance, orange hue can be much fun watching on different devices with greatly varying result especially with respect to red. Some devices give rather yellow instead of orange, other almost the original orange.

Especially the image processing in HDTV sets is a bunch of universes in themselves, albeit sometimes in a positive sense. This makes color grading a difficult task.

thanks for your advices! yeah i m still not very happy with the rendering output, but i m not sure where the mistake is in my signal chain: because i had problems with crashing etc i rendered out some separate scenes before in lossless h264 and then added them together in a new scene to make the final edit.. this might be a source for bad quality, huh? what format would you render lossless to, to not lose quality ? or do you always lose "something"?

I've yet to see a working version of 15.13 (just got the 15.12.1 update for Kubuntu 15.10 AMD 64), so I don't know what these new rendering options look like.

CRF encoding is definitely the way to go with x264, but when you say:

kalimerox wrote:now i try .h264 and put the slider to high quality....

What "quality" (crf) value does the "high quality" slider setting actually correspond to?

You shouldn't see a 15.13 Kdenlive version: this is a developer series. After stable 15.12.3 in March there will be stable 16.04(.0) next in April. Development then will continue with 16.05. Stables are xx.4.y, xx.8.y, and xx.12.y. Development is xx.5, xx.9, xx.13.

Inapickle wrote:What "quality" (crf) value does the "high quality" slider setting actually correspond to?

For the MP4 rendering profile in recent Kdenlive 15.13 development versions, the quality slider setting means..

• worst quality is video:45, audio:64 (kbits)
• best quality is video:15, audio:192 (kbits)

TheDiveO wrote:You shouldn't see a 15.13 Kdenlive version: this is a developer series. After stable 15.12.3 in March there will be stable 16.04(.0) next in April. Development then will continue with 16.05. Stables are xx.4.y, xx.8.y, and xx.12.y. Development is xx.5, xx.9, xx.13.

OK, thanks. Yes, I see there's another Sunab ppa for the developmental version:

https://launchpad.net/~sunab/+archive/u ... enlive-svn

TheDiveO wrote:

Inapickle wrote:What "quality" (crf) value does the "high quality" slider setting actually correspond to?

For the MP4 rendering profile in recent Kdenlive 15.13 development versions, the quality slider setting means..

• worst quality is video:45, audio:64 (kbits)
• best quality is video:15, audio:192 (kbits)

So is the "High Quality" setting that kalimerox referred to = "Best Quality" (crf 15) then ?

I'm just interested to know what CRF value he actually encoded at.

@Kalimerox - also what was the video resolution and frame rate of your rendered project ?

Yes, best quality is high quality in the sense of moving the quality slider to its farest end; unfortunately the slider labels are still not truely descriptive, I thus refer to the end of the quality slider where I also get the highest audio (!) bitrate.

kalimerox wrote:thanks for your advices! yeah i m still not very happy with the rendering output, but i m not sure where the mistake is in my signal chain: because i had problems with crashing etc i rendered out some separate scenes before in lossless h264 and then added them together in a new scene to make the final edit.. this might be a source for bad quality, huh? what format would you render lossless to, to not lose quality ? or do you always lose "something"?

Lossless should be exactly that, it makes sure the output frame matches the input, with x264 you can control a speed / size tradeoff. There are ways you can make a lossless encode lose something, but generally speaking that doesn't happen.

Settings like crf 18 being transparent (as in, you can't tell the difference) is a subjective thing, but one that I agree with except when the framerate is higher. I use crf 15 @ 60fps.

For lossless purposes I use x264 on qp=0 and preset=veryfast for intermediary files.

Maybe some samples would help show the issue you're having?

yes

So is the "High Quality" setting that kalimerox referred to = "Best Quality" (crf 15) then ?

thats the high quality i talked about, i m with

Version 15.13.0 on manjaro / arch, because at the end that was the most stable version i could work with,

but yes the sliders confused me a bit..

good to know that h264 lossless is really lossless and there should not be any difference in editing from the source files or from a lossless h264 conversion.

I had a problem/bug there that my project settings always jump back from 1080p to "automatic" and in auto matic it was just 720p... maybe that explains the quality loss i had, i have to go back on my studio pc to figure that out.

I just wanna mention that this is a great forum with a lot of help, very exceptional the friendly way of helping each other out, thank you all for that!!

kalimerox wrote:...good to know that h264 lossless is really lossless ...

Actually, that's not quite true. Metric quality analyses reveal that when converting YV12 sources to h264 'lossless' , it is lossless with respect to the luma (Y component), but the chroma takes a slight "quality" hit.

The only true lossless YUV formats there in the KDenLive default render options are FFV1 and Matroska.mkv (HuffYUV). However, the MLT presets are configured to encode in YUY2 (4:2:2) colorspace. So configured, these codecs are only lossless in the context of compressing YUY2 input. If they were configured to compress in YV12 colorspace (as both could be) the same would apply - they would only be lossless for YV12 input. Although some lossless codecs are able to receive other colorspace inputs and internally convert to the selected "compression" colorspace, these internal conversions are not lossless. And the same applies to decompression - it is only lossless when the compressed file is being decoded to output in the same colorspace.

In short, whenever there is colorspace conversion, there will always be some degree of quality loss. That's why it needs to kept to a minimum.

kalimerox wrote:I had a problem/bug there that my project settings always jump back from 1080p to "automatic" and in auto matic it was just 720p... maybe that explains the quality loss i had, i have to go back on my studio pc to figure that out.

For sure there will be quality loss if your 1080p source(s) is being edited as a 720p project and rendered out the same. I think that's what your saying has happened ? You mentioned that the size of the rendered file for 60 minutes of video was 4GB. That would put the average bitrate (video + audio) at around 11.4Mbps, which would not be unreasonable for a typical 'mixed content' (in terms of complexity/motion) 720/25p (as assumed ?) source encoded to x264 with CRF 15 (unrestricted).

This reversion of the 1080p project settings to 720p is a bit of mystery though. I'm just wondering if the project was originally set up and saved as 720p and you went in at a later point and tried to change the project settings to 1080p ? Just tried that myself in KDenLive 15.12.1. Set the project up as 720/30p, loaded some clips (mix of 720/30p and 1080/30p) on the timeline and applied some cuts, effects and transitions and saved the project. Then went back in and changed the project settings to 1080/30p, receiving a warning about doing so. Saved and re-opened the project. There was no reversion of the declared project settings to 720/30p, but on rendering out to H264.mp4 the encode was 720/30p. Is it possible that something like that could have happened? Yet you indicate that the project settings also auto-reverted from 1080p to 720p. Strange. Is this "automatic" project setting some new feature in KDenLive 15.13 ?

What resolution/frame rate were your source clips by the way ? The Sony a7s HAVC.mp4 clip that you sent me (to examine the luma scaling) was 720/100p. Were you editing mixed 1080p and 720p sources?