Black border (all round) after bit rate reduction

[Kim_]

I have a 2Gb .mp4 which plays fine on my TV, no borders. It's too big so I recreated it by reducing the overall bit rate from 5000kbps to 1500kbps without changing anything else (using PowerDirector). It plays fine except the image size is smaller on my TV and I have a black border all the way round.

Can anyone suggest why this might happen?

[ProWo]

Post an mediainfo report (text mode) of both movies here

[Kim_]

Thanks for responding ProWO,

Note in these two mediainfo reports there are differences, but the only setting I changed was overall bit rate, any other changes are due to the rendering tool.

Here's the original large file mediainfo:

General
ID : 16727 (0x4157)
Format : MPEG-TS
File size : 1.06 GiB
Duration : 29 min 0 s
Overall bit rate mode : Variable
Overall bit rate : 5 243 kb/s
FileExtension_Invalid : ts m2t m2s m4t m4s tmf ts tp trp ty

Video
ID : 33 (0x21)
Menu ID : 16727 (0x4157)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.2
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Codec ID : 27
Duration : 29 min 0 s
Maximum bit rate : 5 070 kb/s
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate : 50.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709

Audio
ID : 34 (0x22)
Menu ID : 16727 (0x4157)
Format : AAC LC
Format/Info : Advanced Audio Codec Low Complexity
Format version : Version 4
Muxing mode : ADTS
Codec ID : 15-2
Duration : 28 min 59 s
Bit rate mode : Variable
Maximum bit rate : 128 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 SPF)
Compression mode : Lossy
Delay relative to video : -20 ms
Language : English



================================================== ========

And here's the new small file mediainfo:

General
Format : MPEG-4
Format profile : Sony PSP
Codec ID : MSNV (MSNV/isom/mp42)
File size : 337 MiB
Duration : 29 min 0 s
Overall bit rate : 1 622 kb/s
Encoded date : UTC 2021-10-28 17:37:58
Tagged date : UTC 2021-10-28 17:37:58

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.1
Format settings : CABAC / 2 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 2 frames
Format settings, GOP : M=2, N=29
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 29 min 0 s
Bit rate : 1 490 kb/s
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 4:3
Frame rate mode : Constant
Frame rate : 25.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.065
Stream size : 309 MiB (92%)
Language : English
Encoded date : UTC 2021-10-28 17:37:58
Tagged date : UTC 2021-10-28 17:37:58
Codec configuration box : avcC

Audio
ID : 2
Format : AAC LC
Format/Info : Advanced Audio Codec Low Complexity
Codec ID : mp4a-40-2
Duration : 28 min 59 s
Source duration : 28 min 59 s
Source_Duration_FirstFrame : -20 ms
Bit rate mode : Constant
Bit rate : 128 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 SPF)
Compression mode : Lossy
Stream size : 26.5 MiB (8%)
Source stream size : 26.5 MiB (8%)
Language : English
Encoded date : UTC 2021-10-28 17:37:58
Tagged date : UTC 2021-10-28 17:37:58
mdhd_Duration : 1739988

[ProWo]

The new video has an incorrect DAR (Display Aspect Ratio, 4:3 instead of 16:9).
Download clever FFmpeg-GUI, read carefully the notes at first start, then load your new video, click main, click change video DAR, select 16:9 on requested DAR, click change DAR. Done!
No reencode needed, fast and easy.


[Attachment 61497 - Click to enlarge]

[Kim_]

I wonder why PowerDirector decided to do that without my instruction... Oh well... Thanks for this and I will give the tool a go

[Kim_]

Turns out PowerDirector has an aspect ratio setting independent of the input video or timeline, and that's what it uses to create videos. Mine was set to 4:3, once I changed it to 16:9 everything worked fine.

Thanks for your help ProWo