Kdenlive рендер на видеокарте

Hey guys! I am new to using Kdenlive, and have a couple questions. I am using Ubuntu 14.04 with the proprietary drivers.

1. Does Kdenlive have the ability to render using the GPU?

2. Would a newer version of Kdenlive render quicker?

Like I said I’m using Kdenlive 0.9.10 on Ubuntu 14.04 with the proprietary drivers. I’m trying to render a project and it seems to be taking forever. I have a 1 1/2 hour project and it’s taking forever to render (Like 14 hours), when I have a friend with the exact same hardware using Lightworks and he said that he can render the same project in 1 hour. Why is that? Thanks!

Posts 708 Karma 6 OS

Re: Does Kdenlive render using the GPU? & Another question

I switched profiles in 0.9.10 to MLT «properties» (predefined settings). which are actually very oriented towards quality/size and not speed. You can speedup the render by removing the «properties=blablabla» argument in the profile you use, falling back to encoder defaults that are faster.
In recent development, I introduced a «speed» cursor that lets you tune this compromise

GPU rendering is for the moment only for some effects, not very stable, not much faster, and encoding (the heaviest part usually) is still on CPU ; I don’t know if MLT now can use ffmpeg’s hardware H264 encoders.

Re: Does Kdenlive render using the GPU? & Another question

Thanks for the reply! That was really helpful, thanks! What I am wondering, is why Lightworks can export a 1 hour video in 40-50 minutes, but it takes Kdenlive 7 1/2 hours.

When I convert a 1 hour file using Handbrake it takes around 40-50 minutes, but it takes Kdenlive 7 1/2 hours?

Posts 595 Karma 3 OS

Re: Does Kdenlive render using the GPU? & Another question

Maybe because of the rendering settings as Vincent explains? You can always create your own rendering profiles in Kdenlive itself, see the documentation. This way you can use faster rendering presets.

Comparing your Kdenlive project to Handbrake or some other editor is always in the danger of comparing apples to oranges. Your project may consist of a lot of transitions whereas Handbrake only does transcoding. And since there are many different profiles we don’t know what your other editor is set to.

Источник

Rendering¶

Rendering is the process where the edited clips are saved into a single complete video clip. During the rendering process the video can be compressed and converted to a number of different video formats (aka codecs).

The rendering dialog is brought up from the render button from selecting Project ‣ Render menu item or by the Ctrl + Enter shortcut.

Rendering Dialog¶

Изменено в версии 22.04.

Rendering Preset Categories¶

Kdenlive offers many different rendering presets to choose from. The rendering presets are grouped into categories. See picture Above.

Full Project¶

Full Project radio button is the default setting. Kdenlive render from the first clip until the last clip in the timeline.

Selected Zone¶

Selected Zone radio button, Kdenlive will only render that portion of the project which has a selected zone created for it. See Monitors .

Guide Zone¶

Guide zone radio button makes use of Guides to define a region of the project that is to be rendered. See Rendering Using Guides and Rendering Scripts .

Guide Multi-Export¶

Добавлено в версии 22.04.

Guide Multi-Export radio button makes use of Guides categories to be rendered.

The selection of guide categories indicates which guides categories will be considered for rendering. In the example above, there are the following options:

«All Categories»: This leads to four files:

projectname-begin.mp4 (from 00:00:00 to «guide1»)

projectname-guide1.mp4 (from «guide1» to «guide2»)

projectname-guide2.mp4 (from «guide2» to «guide3»)

projectname-guide3.mp4 (from «guide3» to the end)

«Category 0 (purple)»: This leads to three files:

projectname-begin.mp4 (from 00:00:00 to «guide1»)

projectname-guide1.mp4 (from «guide1» to «guide2»)

projectname-guide2.mp4 (from «guide2» to the end)

«Category 1 (blue)»: This leads to two files:

projectname-begin.mp4 (from 00:00:00 to «guide3»)

projectname-guide3.mp4 (from «guide3» to the end)

If guides are behind the last timeline clip, they are ignored.

If a guide sits right at the beginning of the timeline, the name of that guide is used instead of «begin».

If two guides have the same name, an underscore and a number will be added to the file name.

More Option¶

More Option show you more options for rendering.

Render Overlay¶

This option overlays a time code or frame count over the rendered video. This will put the overlay over the entire rendered project. Alternatively you can use the Dynamic Text effect to overlay selected regions of the video.

Export Metadata¶

Check this to have the metadata which has been entered under Project Settings Dialog placed into the metadata of the rendered file.

And this is the metadata on the resulting clip (rendered with Export Metadata checked).

Export Audio Checkbox¶

This is an unusual one. Instead of a normal on/off checkbox toggle, the Export Audio checkbox cycles among three choices.

As if that weren’t confusing enough, the Export audio (automatic) option may appear different depending on your combination of distribution, desktop environment and theme. See three examples below:

Regardless of how the checkbox on the Export audio (automatic) option may appear on your installation, rest assured that when that option is showing, it is enabled.

So what do the three options mean?

Export audio (automatic) means detect if an audio track is present and write the audio track if found

Export audio, when checked, means write an audio track in the rendered file even if there is no audio track to write.

Export audio, when unchecked, means do not write an audio track in the rendered file.

The difference in behavior between enabling Export audio versus Export audio (automatic) can be seen in the situation where you have a video on the timeline but there is no audio track on the timeline and the video in the video track also does not have an audio track. An example of such a situation is shown in the screenshot below.

In this situation, if you render with Export audio (automatic), the rendered file will not have an audio track (Result 1 on screenshot below). But if you render with Export Audio checked, then the rendered file will contain an audio track – the track will however be empty (Result 2 on screenshot below).

FFprobe on file generated from an audio-less track using Export audio (automatic). Note only one stream – Stream #0.0 – a video stream. Kdenlive automatically detected there was not an audio track and so it did not write one.

FFprobe on file generated from an audio-less track using Export audio checked. Note two streams – Stream #0.0 and Stream #0.1 – the latter being an aac audio track. We forced Kdenlive to write an audio track even though there was not any source audio to write.

In cases where there is an audio track …

Rendering with Export audio unchecked will produce a file with no audio track – result 4 in the screenshot above. Rendering with Export audio (automatic) (result 3 in the screenshot above) or with Export audio checked will produce files with Audio tracks.

Encoder Threads¶

Determines the value of Encoding threads passed to melt. For encoding to certain codecs, namely MPEG-2, MPEG-4, H.264, and VP8, kdenlive can use more than one thread and thus make use of multiple cores. Increase this number to take advantage of this feature on multi-core machines. See melt doco — threads and melt FAQ on multi-threading.

Create Custom Render Presets¶

Creates a new preset based on the project profile.

Downloading additional user created presets.

Save the selected preset under a new name.

Save the preset under the current name i.e. replace it.

Will open the Save Render Preset dialog (also shown in the screenshot below) and the Parameters section will be filled in with the render parameters of the preset that you had selected when you clicked either of the or or button. You can edit values in the parameters and save your own custom render preset.

Creating new groups: When you save a preset and enter a group name that does not yet exist, the group will be created.

The parameters are not limited by the UI, you can add custom parameters in the box Additional Parameters under the tab Other .

The parameters in the rendering presets are melt parameters. For an explanation of their meaning, check the melt documentation or type melt -help in a command prompt.

Rendering In Batch mode¶

If you have a lot of rendering jobs to do, you can use Kdenlive to create rendering scripts which you can accumulate and then execute in batch mode overnight. See Rendering Using Guides and Rendering Scripts .

Alternatively, once you have submitted a rendering job on a project and it is up and running in the Job Queue, you can drag the render window out of the way and edit the project some more or load a new project and render that one too. The second render job submitted will go into the Job Queue. Editing the project after a render job is submitted will not change the settings on that job.

Variable Bit Rate — earlier Versions¶

The instructions of this section are probably out-dated please help us to improve the documentation! See Get involved

When a variable bitrate (VBR) profile is selected, the File Size section displays a drop down for choosing the Video quality you want. This quality figure is a codec-dependent number representing the quality of the video that will be rendered. Generally, lower numbers mean higher quality video and larger file sizes (e.g. x264, MPEG2, VPx), but some codecs use opposite order (e.g. Theora). Profiles provided with Kdenlive offer these numbers ordered from best quality (almost lossless) to lower quality (still not degrading too much). The exact file size that is produced can not be predicted when using the VBR method. The idea behind this is that you specify a certain quality of video that you want through the entire video and the encoding optimizes bitrate to give you that constant quality, lowering data size for low action scenes and using more bits for high action scenes.

Example: 1min 55 seconds of 720 x 576 H.264 iPhone footage rendered at quality 15 with the H.264/AAC High Profile would produce a file size of 186 Mb. Whereas rendering the same footage at quality quality 20 produced an 83Mb file.

Constant Bit Rate — earlier Versions¶

The instructions of this section are probably out-dated please help us to improve the documentation! See Get involved

When a constant bitrate (CBR) profile is selected, the File Size section displays a drop down for choosing the Video bitrate you want. This is similar to the version

Источник

Kdenlive рендер на видеокарте