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  1. I am puzzled.
    Maybe it is normal, I don't know, I am not an expert.

    I have .TS files (tv recordings).
    Usually I start some 5 minutes before the actual beginning of the broadcast and add some 10 minutes at the to make sure I don't miss the ending.

    When editing I remove those 'extra' recordings and the commercial breaks, once or sometimes twice during the broadcast.
    All in all, the recording is often reduced by some 30 or 35%.

    I then re-encode the file/export it to a .mkv - high quality (I want to have the same quality as the original recording)
    and end up with a file that often is much bigger than the original 'uncut' one.

    So, a 3.6GB file, minus -say- 30% commercials and stuff, then export to .mkv, I end up with a 4.4GB file.
    The quality is perfect, that isn't the point.

    Added attachment to illustrate what I mean.

    As said, I am not an expert, sorry for the dumb question, but.. is this normal?

    Thanks!

    (using TMPGEnc Video Mastering Works v6, it works perfect)
    Image Attached Thumbnails Click image for larger version

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  2. The definition of average bitrate is
    Code:
    birate = stream size / running time
    hence:

    Code:
    stream size = bitrate * running time
    So if you want a smaller file use a lower bitrate.
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  3. Thank you very much indeed.

    As said, I am not an expert. So, this bitrate stuff, I am sorry ... but need a bit of advice on that.

    In the screenshot above the bitrate in the output was: "Variable"
    Whereas I see that the bitrate in the source was maximum 8,275kb/s.

    I want the quality to be the same as the original, that is most important for me. The filesize, after cutting out commercials, should not be bigger.
    If it is the same file size, then it would be okay, but slightly smaller would be nice.

    Question: what would be the recommended bitrate-settings then?
    Constant?
    and set the 'Maximum' to be the same as the max. in the original?

    See attachments for options #1 #2 #3 and maybe I should use settings in #4

    In this example:
    original file 4.7GB 70 minutes
    removed commercials, left 45 minutes (35% removed)
    the default result, in this example..., would be 3.3GB, which would be fine with me.

    However, as said, in other cases, the result might as well be as big as 2x the original.
    Image Attached Thumbnails Click image for larger version

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    Click image for larger version

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  4. Originally Posted by vhwul62 View Post
    In the screenshot above the bitrate in the output was: "Variable"
    Whereas I see that the bitrate in the source was maximum 8,275kb/s.
    I don't know why MediaInfo didn't report an average bitrate for the new file but it shows a "nominal bitrate" of 10.4 Mb/s. And the x264 metadata shows 10.350 Mb/s was specified. The video is almost exactly an hour long so:

    Code:
    10350000 bits per second * 60 seconds per minute * 60 minutes per second  / 8 bits per byte = 4,657,500,000 bytes = 4.34 GiB.
    That's close to the total file size of 4.44 GiB (remember the file also includes audio and a little container overhead).

    The source file was also an hour long and MediaInfo reports and average bitrate of 8088 Kb/s:

    Code:
    8088000 bits per second * 60 seconds per minute * 60 minutes per second  / 8 bits per byte =  3,639,600,000 bytes = 3.39 GiB.
    Again, that's a little less than the total file size reported by MediaInfo, as expected.

    Originally Posted by vhwul62 View Post
    I want the quality to be the same as the original, that is most important for me.
    That's not possible with lossy re-encoding. The new video will always be slightly lower quality than the source. The higher the bitrate used the closer the new video will be to the source. At some very high bitrate the differences will not be noticeable.

    Originally Posted by vhwul62 View Post
    The filesize, after cutting out commercials, should not be bigger.
    If it is the same file size, then it would be okay, but slightly smaller would be nice.
    Then don't specify a higher bitrate than the source.

    Originally Posted by vhwul62 View Post
    Question: what would be the recommended bitrate-settings then?
    Constant?
    You almost never want to use constant bitrate. If you need a specific file size and want the best quality for that size you should use 2-pass encoding with an average bitrate that will give you the file size you want.

    Originally Posted by vhwul62 View Post
    and set the 'Maximum' to be the same as the max. in the original?
    Minimum and maximum bitrates don't have any effect on the file size. They are used under circumstances where you have playback restrictions (for example, DVD has a limit of 9800 kbps for the video, Blu-ray has a limit of 40 Mb/s). With 2-pass encoding the encoder will allocate more bitrate to shots the need it, less to shots that don't. In the end, the average bitrate will be the value you requested.

    Originally Posted by vhwul62 View Post
    See attachments for options #1 #2 #3 and maybe I should use settings in #4
    You should us Average Bitrate. Under Multipass Settings you should set Pass Count to 2. Under Bitrate/Quality you should set Bitrate to a value that will give the size you want. If you want the file size proportional to size of the original minus what you cut, use the same bitrate as the source.
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  5. Member netmask56's Avatar
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    Probably the software you are using to convert the TS file to MKV. I do much the same using TSDoctor to cleanup the TS file and edit out commercials and top and tail. I save as TS. Then I use MKVToolnix to wrap the TS file in a MKV container. Takes a few minutes, no re-encoding, quality in is quality out and the size is the same..
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  6. I'm a Super Moderator johns0's Avatar
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    If you aren't going to save it and just watch it later then i wouldn't worry about,also it's just a bit bigger.
    I think,therefore i am a hamster.
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  7. @jagabo - Sorry for the late reply. Many thanks again for your elaborate reply, truly appreciate it. I have checked many source .ts files that I have saved and the found bit rate mode: variable and maximum is 10.1Mb/s so probably I should set the bitrate to 10,35 Mbps, which seems to be automatically set by TMPGEnc Video Mastering Works.

    Using 2 pass: I'll consider it. However, to be honest, I don't see a difference between source and the output .mkv using 1 Pass.
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  8. Originally Posted by netmask56 View Post
    Probably the software you are using to convert the TS file to MKV. I do much the same using TSDoctor to cleanup the TS file and edit out commercials and top and tail. I save as TS. Then I use MKVToolnix to wrap the TS file in a MKV container. Takes a few minutes, no re-encoding, quality in is quality out and the size is the same..
    Am using TMPGEnc Video Mastering Works. I have no knowledge of editing and maybe this application is an overkill for the purpose I use it. Often there are cheaper solutions available. Way back and also just recently I gave VideoRedo a try, but found it was (very) slow on moving back and forth and didn't work as comfortable as what I am using.
    A matter of taste, I agree.
    TSDocter and MKVToolNix may be a good alternative for what I am doing. At the time, as a newbie, when getting into video editing arena, the terms used within these tools were entirely new to me, hence they were (too) 'complicated' - I went the easy (GUI) way
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  9. Originally Posted by johns0 View Post
    If you aren't going to save it and just watch it later then i wouldn't worry about,also it's just a bit bigger.
    I save all files - usually they are series.
    After editing I save the jobs into a batch [Batch Encoding] and let Video Mastering Works run and do all, when I am away, or watching TV whatever.
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