Editing 4K content targetting 1080p output
Hi, In my curious "document everything you don't understand in Cinelerra"-adventure. I have now content that is shot in 4K. For speed purposes I am (usually) successfully using the proxy functionality. The proxy is configured to 1/3 of the size (640x360). Problem 1; With the proxy *enabled* I drag a video in the timeline. Since my target format is 1080p I reduce the size of the camera on the video track to Z=0.170 to see the full frame (using the proxy). But when I disable the proxy, the Z value should be set to 0.500 to fill the frame. If I would instead *disable* the proxy, drag a video in the timeline. Set the Z value to 0.500, I am able to start the proxy and get the desired effect that I want: both proxied video and original video are of the same size in the compositor. Problem 2; When the proxy is disabled, the viewer shows the clip in the original resolution. I think this is expected. Now when I enable proxy editing, and then open the same clip in the viewer, the resolution is scaled (zoomed in). It feels like this is all related to the output resolution being 1080p, scaling is applied to the proxy, and the meta data is not used consistently. -- Stefan
On Saturday, January 29, 2022 2:34:50 PM CET, Stefan de Konink via Cin wrote:
Problem 2;
When the proxy is disabled, the viewer shows the clip in the original resolution. I think this is expected.
Nope. It shows it in 1080p, the project resolution. This is not expected from a viewer in my opinion.
Now when I enable proxy editing, and then open the same clip in the viewer, the resolution is scaled (zoomed in). It feels like this is all related to the output resolution being 1080p, scaling is applied to the proxy, and the meta data is not used consistently.
-- Stefan
Stefan, I think you are doing a bit of confusion. When you are using Proxy the Scale factor is used for scale down that video. Your 4k (3840x2160) video, with Scale=1/3 will be scaled to 1920x720, not 640x360. Cinelerra-GG don't know you are using a different Project format (1920x1080) and it is right so. The Z value of the Camera tool don't use pixels but rate. It doesn't matter if Proxy is enabled or not. When Z=0.5 (50% if we want to see it in percentage), the frame will be scaled (up, if Z >1, or down, if Z<1) of that value. It is different for X and Y because them use pixels but the values are switched to the ProjectFormat/ProxyScale. When Proxy is enabled, if you want open a clip in the Viewer, you must dragging and dropping (or double click) that clip from Resources/Proxy, not from Resource/Media. Because your project is 1080p size and you are using a 4k video, the Viewer shows that clip zoomed. The Viewer window aspected a 1080p video, not 4k video. There is a fantastic Workaround for that (... and Thanks GG!!!). Before I write the Workaround, had you thought of one of the two ways below (sorry if I allow mysef)? 1. Using a Project format size for 4k and working onit with Proxy (Scale=1/6?). Rendering out to 4k and, after, converting the Final video with a tool (Handbrake?) or with Cinelerra-GG. 2. Converting your video from 4k to 1080p before loading that video in Cinelerra-GG. You will gain performance after. but loose time for converting. Yes, for #1 and #2, you waste time for conversion. ================== === Workaround === Start from an empty Project 1080p. - In Resources/Media RMB (Right Mouse Button) on the clip icon. - Select "Info..." option. - In Asset info window on "Video:" section, click on "Resize" button and change the Scale to 0.500x0.500. - Enable/Set Proxy. Remember: when Proxy is enabled you must drag &drop (or double click) from Resources/Proxy, not from Resources/Media, to load that clip in the Viewer. ================== Sorry for the long texts. I have to go for a drink because of dry throat. ;-) IgorBeg Il 29/01/2022 14:34, Stefan de Konink via Cin ha scritto:
In my curious "document everything you don't understand in Cinelerra"-adventure. I have now content that is shot in 4K. For speed purposes I am (usually) successfully using the proxy functionality. The proxy is configured to 1/3 of the size (640x360).
Problem 1;
With the proxy *enabled* I drag a video in the timeline.
Since my target format is 1080p I reduce the size of the camera on the video track to Z=0.170 to see the full frame (using the proxy). But when I disable the proxy, the Z value should be set to 0.500 to fill the frame.
If I would instead *disable* the proxy, drag a video in the timeline. Set the Z value to 0.500, I am able to start the proxy and get the desired effect that I want: both proxied video and original video are of the same size in the compositor.
Problem 2;
When the proxy is disabled, the viewer shows the clip in the original resolution. I think this is expected. Now when I enable proxy editing, and then open the same clip in the viewer, the resolution is scaled (zoomed in). It feels like this is all related to the output resolution being 1080p, scaling is applied to the proxy, and the meta data is not used consistently. ... ... ... Nope. It shows it in 1080p, the project resolution. This is not expected from a viewer in my opinion.
Hi Igor, There are multiple reasons not to convert the 4K content to 1080p; 1. Obviously when scaling an h264 file, it must be re-encoded. Since Cinelerra does not support things like 'lossless cut' even it it did every composing step there after will require a re-encoding of the source medium. The quality will degrade. 2. The 4K content allows the editor to crop in post. Hence, I can zoom in, or track content while still having a lot of headroom to do so without loosing visible quality, including rotation. There is a simple reason not to render out 4K; 1. It takes *much longer* to encode H264 in 4K. There are several issues with the proxy. 1. The proxy view looses media. Practically speaking, when by files are in folder A, and I add some files from folder B, my proxy does only contain files from folder B. (this can be seen in the screenshot, but I was not able to reproduce it in the video) 2. As you can see in the screenshot, some of the files that remain have this 'green' thing around the proxy. On Sunday, January 30, 2022 10:33:11 AM CET, Igor BEGHETTO via Cin wrote:
Stefan, I think you are doing a bit of confusion.
When you are using Proxy the Scale factor is used for scale down that video. Your 4k (3840x2160) video, with Scale=1/3 will be scaled to 1920x720, not 640x360. Cinelerra-GG don't know you are using a different Project format (1920x1080) and it is right so.
The 640x360 is what the proxy window shows. I agree that the output for 1/3 should be 1/3 of the input video. But I could *fully* understand that instead -vf scale=w:h is applied to the proxy resolution. I would find that convenient as well.
The Z value of the Camera tool don't use pixels but rate. It doesn't matter if Proxy is enabled or not. When Z=0.5 (50% if we want to see it in percentage), the frame will be scaled (up, if Z >1, or down, if Z<1) of that value. It is different for X and Y because them use pixels but the values are switched to the ProjectFormat/ProxyScale.
I guess this forces me to make a screen recording what I see happening. <https://www.youtube.com/watch?v=emvilPbjNMg>
When Proxy is enabled, if you want open a clip in the Viewer, you must dragging and dropping (or double click) that clip from Resources/Proxy, not from Resource/Media. Because your project is 1080p size and you are using a 4k video, the Viewer shows that clip zoomed. The Viewer window aspected a 1080p video, not 4k video. There is a fantastic Workaround for that (... and Thanks GG!!!).
Is there any technical reason not to have the viewer play any clip in the *media's* resolution. Regardless of proxy or project setup? -- Stefan
Thanks Stefan for screenshots and screencast! For Proxy, could you use .mov, for example, instead of JPEG Sequence (or other type of sequence), please? In your screencast at 2:11 you are dragging and dropping the clip from Resources/MEDIA when Proxy is enabled! Like said in my previous post, when Proxy is Enabled you MUST to use Resources/PROXY. You are changing the Z value of the Camera tool because you have used Resources/MEDIA instead of Resources/Proxy when Proxy is Enabled.
Is there any technical reason not to have the viewer play any clip in the *media's* resolution. Regardless of proxy or project setup? Have have you tried "my" Workflow? May be it is good also for you.
PS: I always use Proxy and it always works right! Pay attemption becouse some plugins, like Title, are not developed for Proxy. IgorBeg
On Sunday, January 30, 2022 2:02:36 PM CET, Igor BEGHETTO via Cin wrote:
Thanks Stefan for screenshots and screencast!
No problem, this makes it all easier too see where it goes wrong.
For Proxy, could you use .mov, for example, instead of JPEG Sequence (or other type of sequence), please?
Ok, will try.
In your screencast at 2:11 you are dragging and dropping the clip from Resources/MEDIA when Proxy is enabled! Like said in my previous post, when Proxy is Enabled you MUST to use Resources/PROXY.
You specifically mentioned the viewer. Is there a technical reason this cannot be used completely transparently? If a proxy media is available for the asset, use that media when proxy editing is available?
Is there any technical reason not to have the viewer play any clip in the *media's* resolution. Regardless of proxy or project setup? Have have you tried "my" Workflow? May be it is good also for you.
I have not yet tried to do the resize with info. But: that is actually beyond my question. Is there a reason why media wouldn't just play any format at its native resolution?
I always use Proxy and it always works right! Pay attemption becouse some plugins, like Title, are not developed for Proxy.
Thanks for this "warning" :) -- Stefan
Is there a technical reason this cannot be used completely transparently? If a proxy media is available for the asset, use that media when proxy editing is available? It has been requested many time ago but it was not possible.
I have not yet tried to do the resize with info. But: that is actually beyond my question. Is there a reason why media wouldn't just play any format at its native resolution? I think there is a reason. Meanwhile I use what We have. I can only help you with my workaround.
Today I close. Bye! IgorBeg
participants (2)
-
Igor BEGHETTO -
Stefan de Konink