VP15, build 361
1. Create project, put short single 1080p fragment on timeline (I put 1080-50p, ~12 sec)
2. Render it using Magix AVC with default profile Internet HD 1080p with average bitrate 20 000 000 and encode mode -- AMC VCE Default. Name file '1.mp4'. Notice the file size and check the file's media info. In my case file size is 34.1 MB, bitrate - 21.9 Mb/s.
3. Render it (again) using the same encoder/profile/settings but average bitrate increased to 40 000 000. Name file '2.mp4'. Notice the file size and check the file's media info. The file size and media info bitrate should be noticeable bigger than in step 2. In my case file size if 64.5 MB, bitrate - 41.5 Mb/s.
4. Render it (yes, again. 3 is lucky number) using the same encoder/profile/settings as on step 2. Name file '2.mp4'. Overwrite? 'Yes'. I was expecting that 2.mp4 is overwriten and resulting file size would be the same size as 1.mp4. However, in my tests resulting file size is exactly the same as it was after step 3 (64.5 MB), but bitrate shown by media info is as for 1.mp4 (21.9 Mb/s). Also, file 2.mp4 is not played correctly.
Looks like AMD VCE renderer does not truncate the file correctly when overwriting.
Checked with Mainconcept AVC encode mode -- everything OK.
Anyone can double check?
P.S. Win 10 Pro 64bit 1803, graphics card RX470 (driver version 18.5.1)
I just ran a test on AMD VCE 1080 30P I re-rendered twice and the file size is the same here. But AMD VCE won't let me overwrite the previously render file name. But if I render it and create a different file name, then its ok to render.