H264 recompression - does extra bitrate help?

[gs684]

I am editing some files that are already in H264 format. The source I am editing is 30fps 1080p at roughly 8.5 mbps bitrate. My output will also be H264 format, so obviously there will be inevitable degradation from the lossy recompression process. I am wondering whether it's possible to help to alleviate some of that degradation by providing some extra bitrate. For example, the 8.5mbps of the current source is a typical bitrate for 1080p video and it's approximately the same bitrate I would use for this if I were encoding original raw footage. But since I am recompressing already encoded video here, if I export at a higher bitrate than the original (e.g. 12-15mbps), will that help with the quality? What would be the bitrate ceiling before anything extra becomes useless?

[poisondeathray]

Yes, a higher bitrate will result in less quality loss for a given encoder and settings used

The settings and encoder also make a difference e.g using 12Mb/s using a bad encoder or bad settings will not look as good as using a good encoder or good settings

There is no real bitrate ceiling, except for the bitrate achieved during lossless encoding if you're using an h264 encoder that supports lossless (e.g. x264). But there are diminishing returns for higher bitrate in terms of viewer perception - there will be a bitrate range where it's visually lossless to a given viewer, but you cannot necessarily determine that beforehand. It also depends on the person viewing - for some they cannot distinguish between something low quality, like youtube with half the bitrate you are using.

[rgr]

I am editing some files that are already in H264 format. The source I am editing is 30fps 1080p at roughly 8.5 mbps bitrate. My output will also be H264 format, so obviously there will be inevitable degradation from the lossy recompression process. I am wondering whether it's possible to help to alleviate some of that degradation by providing some extra bitrate. For example, the 8.5mbps of the current source is a typical bitrate for 1080p video and it's approximately the same bitrate I would use for this if I were encoding original raw footage. But since I am recompressing already encoded video here, if I export at a higher bitrate than the original (e.g. 12-15mbps), will that help with the quality? What would be the bitrate ceiling before anything extra becomes useless?

In that case, I always give a bitrate 10% higher. Visually it comes out like the original.
Unless I correct the video at the same time - then I save with CRF 19 set.