{"action":"created","issue":{"url":"https://api.github.com/repos/donmelton/video_transcoding/issues/108","repository_url":"https://api.github.com/repos/donmelton/video_transcoding","labels_url":"https://api.github.com/repos/donmelton/video_transcoding/issues/108/labels{/name}","comments_url":"https://api.github.com/repos/donmelton/video_transcoding/issues/108/comments","events_url":"https://api.github.com/repos/donmelton/video_transcoding/issues/108/events","html_url":"https://github.com/donmelton/video_transcoding/issues/108","id":197603990,"number":108,"title":"Proposal to modify `--quick` and/or add `--veryquick` option","user":{"login":"donmelton","id":115488,"avatar_url":"https://avatars.githubusercontent.com/u/115488?v=3","gravatar_id":"","url":"https://api.github.com/users/donmelton","html_url":"https://github.com/donmelton","followers_url":"https://api.github.com/users/donmelton/followers","following_url":"https://api.github.com/users/donmelton/following{/other_user}","gists_url":"https://api.github.com/users/donmelton/gists{/gist_id}","starred_url":"https://api.github.com/users/donmelton/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/donmelton/subscriptions","organizations_url":"https://api.github.com/users/donmelton/orgs","repos_url":"https://api.github.com/users/donmelton/repos","events_url":"https://api.github.com/users/donmelton/events{/privacy}","received_events_url":"https://api.github.com/users/donmelton/received_events","type":"User","site_admin":false},"labels":[{"id":208117324,"url":"https://api.github.com/repos/donmelton/video_transcoding/labels/enhancement","name":"enhancement","color":"84b6eb","default":true}],"state":"open","locked":false,"assignee":{"login":"donmelton","id":115488,"avatar_url":"https://avatars.githubusercontent.com/u/115488?v=3","gravatar_id":"","url":"https://api.github.com/users/donmelton","html_url":"https://github.com/donmelton","followers_url":"https://api.github.com/users/donmelton/followers","following_url":"https://api.github.com/users/donmelton/following{/other_user}","gists_url":"https://api.github.com/users/donmelton/gists{/gist_id}","starred_url":"https://api.github.com/users/donmelton/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/donmelton/subscriptions","organizations_url":"https://api.github.com/users/donmelton/orgs","repos_url":"https://api.github.com/users/donmelton/repos","events_url":"https://api.github.com/users/donmelton/events{/privacy}","received_events_url":"https://api.github.com/users/donmelton/received_events","type":"User","site_admin":false},"assignees":[{"login":"donmelton","id":115488,"avatar_url":"https://avatars.githubusercontent.com/u/115488?v=3","gravatar_id":"","url":"https://api.github.com/users/donmelton","html_url":"https://github.com/donmelton","followers_url":"https://api.github.com/users/donmelton/followers","following_url":"https://api.github.com/users/donmelton/following{/other_user}","gists_url":"https://api.github.com/users/donmelton/gists{/gist_id}","starred_url":"https://api.github.com/users/donmelton/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/donmelton/subscriptions","organizations_url":"https://api.github.com/users/donmelton/orgs","repos_url":"https://api.github.com/users/donmelton/repos","events_url":"https://api.github.com/users/donmelton/events{/privacy}","received_events_url":"https://api.github.com/users/donmelton/received_events","type":"User","site_admin":false}],"milestone":null,"comments":8,"created_at":"2016-12-26T16:47:32Z","updated_at":"2016-12-27T15:37:08Z","closed_at":null,"body":"# Proposal to modify `--quick` and/or add `--veryquick` option\r\n\r\nEarlier this month, I significantly increased the the speed and quality of the original `--quick` option. Encoding is now 70-80% faster than the default setting with no easily perceptible loss in video quality.\r\n\r\nBut I can't seem to leave well enough alone. :)\r\n\r\nI now have a formula to increase encoding speed by 90-125% over the default setting. And _still_ with no easily perceptible loss in video quality.\r\n\r\nYou can try this proposed implementation yourself. Don't use `--quick` since that will invoke the current implementation. Instead add five new `--encoder-option` (or `-E`) arguments to your command line like this:\r\n\r\n```\r\ntranscode-video -E partitions=none -E ref=1 -E bframes=1 -E rc-lookahead=30 -E me=dia \"/path/to/Movie.mkv\"\r\n```\r\n\r\nThese five x264 video encoder settings are listed in order of their impact on performance with `partitions=none` being first since it gives the biggest boost.\r\n\r\nThe two new additions over the current `--quick` implementation are `bframes=1` and `me=dia`. It's `bframes=1` which adds the biggest new boost and demonstrates the cost for all that additional speed. Like `ref=1`, also part of the current `--quick` implementation, the `bframes=1` setting reduces the efficiency of the x264 encoder, meaning it takes more bits to encode the same quality.\r\n\r\nBut since my special ratecontrol is constrained by both target bitrate _and_ minimum quality, `bframes=1` doesn't reduce quality very much at all. At least not in a way that's easily perceptible. Instead, output bitrate increases somewhat. And if a video would exceed the target bitrate a little with the default setting, it will now exceed it a little more. And if it would exceed it a lot, it will now be a lot more.\r\n\r\nNormally you would see less than a 1% increase in bitrate. Sometimes more than 1%. The worst case scenario might be a 10% increase. But, so far, I've only seen one movie go over 5%. So maybe the slightly larger size is not something to worry about.\r\n\r\nOne curiosity with the new formula is the large range of the possible speed increase: 90-125%. This is because some Blu-ray Discs contain video in VC-1 format instead of H.264 or MPEG-2. And HandBrake takes significantly longer to decode VC-1 format than the others.\r\n\r\nIf I were to exclude input files with VC-1 format video, the speed increase would be 110-125%. Now we can all be annoyed at Microsoft for inventing VC-1 and Warner Bros. for using it on their discs for so long. :)\r\n\r\nThe big question is: should this new formula replace the current `--quick` option or should I add a new `--veryquick` option to implement it?\r\n\r\nI don't usually like to add new options but I'm concerned that some users might object to the possibility of slightly larger output bitrates with the new formula. And the new formula may seem like lower quality to those users, especially for DVD-sized content. Beauty is, after all, in the eye of the beholder.\r\n\r\nBTW, if I do add a `--veryquick` option then I'll likely modify `--quick` anyway to remove the `mixed-refs=0` setting it currently uses. It turns out that setting is unnecessary when the `ref=1` setting is also applied.\r\n\r\nAnyway, let me know what you think. Soon. Because I'm liable to make the change shortly after the first of the new year.\r\n\r\nThanks."},"comment":{"url":"https://api.github.com/repos/donmelton/video_transcoding/issues/comments/269341512","html_url":"https://github.com/donmelton/video_transcoding/issues/108#issuecomment-269341512","issue_url":"https://api.github.com/repos/donmelton/video_transcoding/issues/108","id":269341512,"user":{"login":"donmelton","id":115488,"avatar_url":"https://avatars.githubusercontent.com/u/115488?v=3","gravatar_id":"","url":"https://api.github.com/users/donmelton","html_url":"https://github.com/donmelton","followers_url":"https://api.github.com/users/donmelton/followers","following_url":"https://api.github.com/users/donmelton/following{/other_user}","gists_url":"https://api.github.com/users/donmelton/gists{/gist_id}","starred_url":"https://api.github.com/users/donmelton/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/donmelton/subscriptions","organizations_url":"https://api.github.com/users/donmelton/orgs","repos_url":"https://api.github.com/users/donmelton/repos","events_url":"https://api.github.com/users/donmelton/events{/privacy}","received_events_url":"https://api.github.com/users/donmelton/received_events","type":"User","site_admin":false},"created_at":"2016-12-27T15:37:08Z","updated_at":"2016-12-27T15:37:08Z","body":"@RodBrown1988 Yeah, I probably should mention the slightly lower quality. It's really hard to detect because it doesn't manifest itself with artifacts, color banding or as blockiness. It's just... not quite as good in a way that's both hard to see and hard to describe.\r\n\r\nHow about I change the line that says, \"with no easily perceptible loss in video quality\" to \"with _little_ easily perceptible loss in video quality?\""}}
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