Some have pointed the finger of blame at edit software, specifically Final Cut Pro X. Reds are most affected, but these issues crop up in areas of strong chrominance including fabrics, graphics and stage/theatrical lighting. These are wasting bitrate and robbing the image of crispness and detail. Like ‘true’ interlacing artefacts, these stripey areas add extra ‘junk information’ which must be encoded and compressed when delivering video in web ready formats. These artefacts illustrate that there’s some interlace going on even though the image is progressive. There are stripes at the edge of the red peppers, and their length denotes interframe movement. Please click the images to view them at the correct size: This is a 200% frame of some strongly coloured (but natural) objects, note the peculiar pattern along the diagonals – not quite stair-stepped as you might imagine. I’ve never seen this in Panasonic or Sony implementations of AVCHD. Note that this problem is completely separate from the ‘Malign PsF’ problem discussed in another post, but as the C100 is the only camera that generates this particular problem in its internal recordings, I suspect that this is where the issue lies. However, stronger colours found in scenes common to event videographers, and when ‘amplifying’ colours during grading, all draw attention to this artifact. Normally, our eyes aren’t so bothered about this, and most of the time nobody’s going to notice. AVCHD is 4:2:0 – the resolution of the colour is a quarter of the resolution of the base image. This all seems bizare and unnecesary in a professional piece of software however we got there after several hours of experimenting.The C100’s AVCHD is a little odd – you may see ‘ghost interlace’ around strong colours in PsF video. Then guess what the output file went back to 192Mb with no visible loss of quality. Taking this file into Handbrake with settings:įast 1080p30 everything else as standard except I moved Average Bitrate in Handbrake to 3000. Then looked at the variable bit rate in original file and matched it roughly in the Bit rate settings with 2 passes. I exported out of Premiere with the settings as: So after I experimented exported twenty times, with tweaks in the bit rate and variable bit rate this is what I discovered. However it didn't really resolve the problem of why a 116Mb screen captured training video becomes 633Mb after a small edit in Premiere. Hmm.Īfter seaching online for an answer to this problem of edited video file sizes, I found this post. I feel like a tech genius would have had a definite answer that's obvious to them. I don't like this approach, of course, and would like to get better AME settings to render small files.ĭoing highly compressed files creates unusable garbage that's worse than the original and still far larger. Weird workaround I've used out of desperation: upload to YouTube and then download that file since YT has good compression. But even with a file at 25fps that I just worked on it was the same issue. Especially true with webinar files since AME can't run at that low of a framerate. I'll end up with ridiculously large files, even if the vid is half the original length and I export with matching settings ticked. I know little of the advanced settings, but can attest that I also wind up with HUGE file sizes and it's been an ongoing issue for years.Ī lot of times, I'll get files that people create through Camtasia or via webinar recording and they ask me to trim them down and add our corporate bumper. Welcome to 2019! Still no good answer on this topic. I honesty know little about the advanced H.264 settings, but perhaps changing Profile (like Baseline vs Main) or the Keyframe distance might yield better results? I just don't understand the nuts and bolts of setting up an H.264 encode optimized for your needs, but that may be the key to better quality at smaller file sizes for what you are doing. I think that is what you are running into here. It is not ideal for compressing a static computer screen, or white box with text. The H.264 codec must be optimized for VIDEO, which normally has a LOT of changes from frame to frame due to movement of camera and subjects. Years ago, I created some training tutorials using Camtasia and was able to get fantastic quality at small file sizes. In that way, the recording could be extremely small and still have a nice image. What format was the original clip? Seems that the screen cap software would use a codec specifically optimized for computer screen capture, meaning very little or even nothing changes frame to frame, for instance ONLY the mouse pointer moves and entire rest of the screen is unchanged. It appears to me from the image in initial post that the OP was using some sort of screen capture software to create the original clip.
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