Thanks to David, Haldun and Felix for their comments and suggestions. See my comments below. ------ David Armstrong <[email protected]> wrote: Murray,
As per Felix and Haldun's reply, the trick is to transcode the raw video into a codec that Cinelerra likes. Haldun ALTAN <[email protected]> wrote: Hello, I'm on Ubuntu studio 10,04 / 64 and I use EKD (you can get it from synaptics) to transcode HD files on DNxHD to use them in cinelerra. It works OK. (sound and images.) Then follow instruction on Grandma to render in best quality. For me it works. Haldun It took me a while to figure out how to download and install EKD. It appears that it is only available in French. However, I did find some English documentation on the internet. Nevertheless, I have found that my .mp4 video shows up with weird colours (skin tones are blue/green). I see this is also the case in some video viewers, such as VLC. They are OK in Gnome Player, and some others. Thus, I reverted to using ffmpeg. If I remember correctly, I did something like: $> ffmpeg -i {input_file.mp4} -b 8500k -s hd1080 {outputfile.mov} and it seemed to work OK (the q factor seemed to be around 8 -- I would prefer to get it down to 2). The resulting file looks good in Gnome Player, and also in my Windows software. However, when I load it into Cinelerra, in the compositor it only shows a central section of the video. It looks OK on the timeline, and the colours look fine. I tried playing with things like zoom, project preferences, etc. but could not get the compositor to show the full frame -- any idea what I am missing there? -------- felix <[email protected]> wrote: Hi Murray My work flow with Cinelerra first involve converting my video files to an intermediate codec: Mjpeg. I use the program ffmpeg with a command line similar to: ffmpeg -i input_file -vcodec mjpeg -qscale 0 -s 1920x1080 -pix_fmt yuvj420p -acodec copy output_file I use a .mov extension for the output file I then load the files in Cinelerra and edit them. For rendering I use the following settings: File format: Quicktime for Linux audio track rendering: Twos complement, 16 bits Video: YUV 4:2:0 Planar This produces very large files, of about 4 Gig/ minute for 1080p I then use ffmpeg again to convert the video to a format that I will use elsewhere. For instance to upload video on vimeo and covert it to 720p, I use ffmpeg -i input_file -vcodec libx264 -vb 2000k -s 1280x720 -acodec libmp3lame -ab 256k output_file This work flow has been working for me, you can experiment with different settings in terms of codecs, bitrate, qscale and others settings to get the file format that you need. There is also the Arista transcoder to convert files from one format to an other. It has presets for common displaying means: pc, tablet, phones, etc. Hope it helps Félix-A. Thanks for your hints, Felix. I will have to try to learn (relearn???) what options to use for ffmpeg. However, using the settings above and outputting to .MOV looks like a good, easy first step if I could only figure out why it seems to show only the central section of the video in the compositor, I could begin to try to use it. - - - - - For 720p, I convert the video to quicktime format and dnxhd codec (see Grandma for details). Cinelerra doesn't like non-standard video aspects, so also make sure they are standard 1280x720 or 1920x1080 etc. It will accept ".mts", but that is transport stream with a long GOP format, which can cause various issues of sync'ing and applying effects. Converting from a long GOP to a non-GOP format will obviously gobble up more disk space, but that is the trade-off for quality and stability in editing. For large or complex projects, I will render a block of video and import into a parent project. But to do this, the rendering has to be as high as possible to prevent obvious degradation. Render to quicktime with MJPEG is what I use there. Is this with Cinelerra, or with ffmpeg? If the latter, could you please give me an example of your ffmpeg command to do this? Thanks. On final render, you choose whatever is appropriate. For the web, I will output to quicktime with mpeg-4 vid and audio codecs. This is a good balance between quality and size. I read with interest the format Felix uses for output (so many options). And FFMPEG is really useful, but another tool that has so many strings. As others point out, there is a lot of flexibility that will cause grief when you get it wrong. Keep experimenting, and when you understand the control you have, the possibilities are endless. cheers David Thanks again for the replies. Murray
