This is my first post!

Congratulations for the development of Kdenlive. It is a great video editing software.

I did a reading on the website and did some test with Kdenlive, now I have some suggestions to improve the software:

The main goal of using a free software is to save money, so it is important to make the software to work good in cheap computers which would help to save money also. To build a new machine today, the cheapest processors to use Kdenlive (or also the Shotcut) are the Celeron G1820, G1830, G1840 and G1850. They are dual core from 2.7GHZ to 2.9GHZ, enough to decode and playback the AVCHD and MP4 video files from HD DSLR, Mirrorless and Camcorders in Kdenlive. Also these processors can avoid buy a discrete GPU because they have the updated OpenGL in the video drivers to use the hardware acceleration for effects in Shotcut software. The following idea also consider a cheap computer will have just one monitor, not the dual monitor configuration, a cheap low budget machine.

Considering that the CPU is the hardware which does the video decoding when playback in timeline, these dual core Celeron processors are enough to playback one AVCHD video layer in the software timeline in realtime, no drop frames. Also some small transitions between two clips can work in preview because video transitions are just a few frames in duration. So a Celeron Haswell machine can work perfectly for most video productions which uses just one main video layer most of times.

The problem comes in the effects moment. The OpenGL can help to see some effects in realtime, but not so many effects together, and there are some effects which are very hard to preview even using OpenGL. Some effects can use OpenGL, but not all. Also just Shotcut is implementing OpenGL, Kdenlive does not but it is an awesome software, so the idea is:

In Both Kdenlive and Shotcut there is the option to see the video in 100% size or in 50% size. The idea is to implement the 25% size and the 33% preview size. But not just to change the image size in preview, but also to reduce the number of pixels which are being processed with the effects, no matter if the CPU or GPU is doing the job. This can help the preview to be realtime or almost realtime.

After the processor decodes the full size video (1920 x 1080), the software could preview the effects using less pixels, (480 x 270 = 25%) or (640 x 360 = 33%) or (960 x 540 = 50%) this can make the preview playback to be real time without drop frames for some simple effects like contrast, brigtness, gamma, saturation, hue, which are the most important. And also make the hard effects almost realtime, in a smaller window, but enough to see the results before render. These small resolutions are what most people see in smartphones, tablets, laptops, notebooks, in Youtube and Vimeo, so these preview sizes are also useful to perceive how the video will look in small screens, 480x270 and 640x360 are very common in youtube and vimeo. This idea is something like half resolution preview, third resolution preview, quarter resolution preview.

This feature can make a very cheap low budget computer to be a perfect workstation for video production using Kdenlive or Shotcut. Kdenlive would be much faster in preview effects using this idea because it does not have GPU acceleration.

Thanks for reading, and I hope this can be useful for the softwares improvement.

Hello & welcome,

The main goal of using a free software is to save money

Not only. Some people feel concerned by the freedom it brings (ability to know what the program is really doing, to make it evolve etc).

Shotcut is implementing OpenGL, Kdenlive does not

Movit (OpenGL filters) was first tested in Kdenlive, but was removed from master branch to take the time to make this evolution more stable. It should come back during 2015 with the Frameworks 5 version

not just to change the image size in preview, but also to reduce the number of pixels which are being processed with the effects

This is what proxy clips are for. Tune your proxy settings according to your hardware power (&effects complexity) and you can preview your project in real time on low end computer!

kdenlive allows to change the preview window size steplessly by dragging the surrounding borders. The opportunity to set it to some percentage would save a few minutes, though.

Thanks for the comments and suggestions!

I did a read in the proxy instructions, very good, well done. I got the idea of click in an icon in the clip in timeline to enable/disable the proxy, this way we can see full resolution if needed, The icon in clip in timeline makes it more ease and fast to enable/disable the proxy for each clip, or an icon in timeline to enable/disable all proxy, maybe this already exists in the software...

Good to know the OpenGL will come to Kdenlive, and I like the freedom felling also, I am starting to love the linux world.

Drag the borders works ok, and yes, the size options can make it more fast and precise to do, I also did a draw to explain the low resolution preview, I think it is obvious but the draw can help to understand, showing the effects applied before or after the resolution change and compared to proxy, please see:

https://www.dropbox.com/s/8gvz4kc9w4qwbpz/3tp.png?dl=0

Good to know about the 15.04 new version and the upcoming 15.08 I did not try yet, waiting a distro with it.

I found a way to get a fast monitor window size changing. First I learned how to tweak the audio/video compression for the proxy, so I can generate proxy 320x180, 426x240, 480x270, 640x360, 854x480, 960x540 and so on... with lower compression level to get better quality

I open the proxy clip with VLC and put it over kdenlive, then I mark the pc monitor with the finger and change the kdenlive monitor size to the same size of VLC media player, after this I save the screen layout. When I want to change the monitor window I just load another screen layout.

This solution makes me to think about to have an option, instead of percentage (100%, 50%, 44,44%, 33%, 25%) It would be easy to have: "Set Monitor Window to Proxy Size" and also "Set Monitor Window to twice the Proxy Size" (for split playback, four clips simultaneously)

Or we could have the sizes: 960x540, 854x480, 640x360, 480x270, 426x240, 320x180... in the monitor menu.