Combined offline/online workflow with Lightworks Posted by gkocov - 17 Dec :55

Transcription

1 Combined offline/online workflow with Lightworks Posted by gkocov - 17 Dec :55 Here's an easy way to do a combined offline/online file based type of workflow in Lightworks: First convert the raw material (for ex. RED R3D files) to a low resolution, low bit-rate format and place all the video files inside one folder (let's call it 'used_video'). Import the files in Lightworks by linking to them and then do the offline edit/color/effects as you normally would (be sure that you can remove any rendered effects with Reconfigure). After you've finished the offline edit, roll back the rendered effects, close Lightworks and rename the folder with the video files (for ex. to 'unused_video'). Reconvert only the takes used in the edit from the raw material, but now to a high resolution, high bit-rate format and place the newly converted high quality files in the same folder where you originally placed the low quality files (i.e. 'used_video'). Also, while reconverting be sure that the low quality and the high quality video files of the same take have the same file names. Reopen the Lightworks project and you should have the newly created files automatically relinked to the Lightworks clips. Not only you can transparently mix files with different resolutions, bit-rates and/or codecs, but you can also switch the project resolution format at any time and Lightworks will transparently adapt the output accordingly. That way you can first edit in high res, then switch to low res to work in realtime with lots of layers/effects/etc., and finally render the effects and switch back to hi res to continue the edit. Posted by khaver - 17 Dec :01 I tried this by creating a 1920x1080 project. I imported my 640x360 offline files into the project and made my edits, etc. I left the project and swapped in my same named HD files in place of the low res files. I re-entered the project but all the video showed as zoomed in to a 640x360 windows of my hi-res files. Are you saying I should set my project to a low-res, do my edits, leave the project, swap the files, re-enter the project and change the res of the poject? I'll try it. Posted by Hammerhead - 17 Dec :20 1 / 6

2 Hi Khaver. I'm not sure that Lightworks will tolerate changes in image dimensions if you stealthily switch the footage - this is because a whole host of metadata (about dimensions/pixel-aspect-ratio/etc) is obtained at import/ingest time and stored outside of the media files themselves. Traditionally in Lightworks, the proxy workflow would go something like : - import your low-res proxies - make your edit - import your full-res clips - use the 'find material to fill edit' feature to repopulate your edit with the full-res clips Bear in mind that the timecodes for the low/high-res files have to match for this workflow to succeed. Posted by khaver - 17 Dec :51 I just tried the stealth swapping method with 1920x1080 UT Codec YUV422 intermediates and 640x360 the same codec proxies (I have a utility that creates both from my HDV sources). It worked without having to change the project res (I couldn't change the project res because there are no low-res 24p projects in the list). First, I had my proxies in my working directory along with the WAV files. I imported the proxies into my 1920x p project. Did a few quick edits and some color correction. Left the project going back to the lobby. Swapped the hi-res intermediates in place of the proxies and re-entered my project. All tile and edit viewers looked normal except now I could tell they were the hi-res versions (no pixelation in the Big viewer or Full Screen view like the proxies showed). Hammerhead, please don't change this. It's a feature, not a bug. Posted by Hammerhead - 17 Dec :40 2 / 6

3 I'm glad that it works! It sounds like you're probably fine as long as the pixel aspect-ratio doesn't vary between the proxy & the full-res version. Posted by gkocov - 18 Dec :22 Even mixing different pixel aspect ratios works. Just tried using PAL 16:9 (pixel aspect ratio 1.45) as proxy footage and then swapping it with a 1080 version (square pixel aspect ratio) and there were absolutely no problems. Posted by Hammerhead - 18 Dec :28 It will 'work' with any alternate footage, but bear in mind that different formats can have different active areas, and Lightworks will base all its display logic on the format that was specified at import time. (eg. in HD1080, all the pixels are active, but in SD576 there are nine inactive pixels at either end of each scan line, etc). AS long as you're aware of this, you should be fine. Posted by gkocov - 19 Dec :31 I see. Thanks for the explanation. Posted by frear - 08 Jun :33 Hello, I've tried the UT off/online workflow without success. Transcoded from Panasonic's mts via avisynth + VD. Hi res UTs are a heavy edit for my pc, so I have 640*360 proxies ready for use. They are ok and play fine in players. 3 / 6

4 Swap & reswap also work smoothly. But.. The proxies show up green in LW! Any help? Posted by khaver - 08 Jun :02 The proxies need to be 720x480. They will stretch to 16:9 in your project. Also, you need to first import your full res video clips, close Lightworks, swap your proxies in, and start Lightworks and enter your project. You should now be able to edit using the proxies. When you're ready to export, close Lightworks, swap back your full res files and go back into Lightworks. Posted by Greg_E - 08 Jun :18 I would say that this needs to be a requested feature to have the quarter resolution proxies for 1280x720 and 1920x1080 supported. In fact an automatic proxy generation in the import window would be really nice, and then an automatic proxy to full substitution tool would be great too. It will handle some proxy sizes, but I don't remember what they are, smaller than NTSC/PAL SD frames is all I remember. Posted by frear - 09 Jun :18 Thank you, working now. Despite the transcoded file size (20 times the original, or "just" 5 times for proxies) UT decodes fast and this workflow allows working on my machine. 4 / 6

5 Moreover keeping the same codec makes experimenting CC with proxies possible. Just... despite my HD clips are already deinterlaced, LW shows "1080i" in the format field when importing. Did you get the same issue? Posted by jwrl - 09 Jun :11 frear wrote: despite my HD clips are already deinterlaced, LW shows "1080i" in the format field when importing. Did you get the same issue?that's probably because they are. 1080p25 and 1080p30 are interlaced formats. The motion content in both fields is the same, hence the term "progressive", but it is an interlaced format. Posted by frear - 09 Jun :51 This is my AviSynth routine for 1080i50 -> 1080p25: directshowsource("00000.mts").assumetff().separatefields() x0 = selectevery(2, 0,1).Weave().ConvertToYUY2() return(x0) It splits, then puts together the frames (from panny's mts 25p into 50i container). To my eyes, it should be 25 fps progressive. Posted by khaver - 09 Jun :59 5 / 6

6 If the source video is 25p wrapped in 50i, why are you separating the fields then re-wrapping (weave) back into 50i? If you want true 25p from your 25p in 50i footage just use: directshowsource("00000.mts").assumeframebased().converttoyuy2() Then create a 25p project in Lightworks. If your footage is just 50i and you want 25p you need to use a true motion interpolating de-interlacer. 6 / 6