How to detect if MPG2 is upgraded mp4 (h264)?

[Spiny Norman]

Recently I was given a video file in mpg2 quality and I rather suspect it's a youtube download "upgraded" to mpg2.
Is there any way to detect this? I mean other than purely visibly, does it leave any telltale traces? Any useful answers will be very much appreciated.

One more thing, it was pillarboxed AND set to 4:3 so that youtube displays it doubly pillarboxed (taller than it is wide). The pillarboxing has been cut off completely in the mpg2, but in itself that doesn't prove anything since that could have been done to any source format.
I extracted the following data:

File Size (in bytes) ............................: 1,473,114,112 bytes
Runtime ............................................: 23:24.960

Video Codec ...................................: MPEG-2
Frame Size ......................................: 720x576 (AR: 1.333)
FPS .................................................: 25.000
Video Bitrate ...................................: 6693 kb/s
Bits per Pixel ...................................: 0.646 bpp
B-VOP, N-VOP, QPel, GMC.............: [], [], [], []

Audio Codec ...................................: DVD_LPCM_AUDIO
Sample Rate ...................................: Hz
Audio Bitrate ...................................: kb/s [ channel(s)]
No. of audio streams .......................: 1


Format : MPEG-PS
File size : 1.37 GiB
Duration : 23mn 24s
Overall bit rate mode : Variable
Overall bit rate : 8 388 Kbps
Writing library : (dvd5: Oct 27 2015)

Video
ID : 224 (0xE0)
Format : MPEG Video
Format version : Version 2
Format profile : Main@Main
Format settings, BVOP : Yes
Format settings, Matrix : Default
Format settings, GOP : M=3, N=12
Format settings, picture structure : Frame
Duration : 23mn 24s
Bit rate mode : Variable
Bit rate : 6 685 Kbps
Maximum bit rate : 9 800 Kbps
Width : 720 pixels
Height : 576 pixels
Display aspect ratio : 4:3
Frame rate : 25.000 fps
Standard : PAL
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.645
Time code of first frame : 00:00:00:00
Time code source : Group of pictures header
GOP, Open/Closed : Open
GOP, Open/Closed of first frame : Closed
Stream size : 1.09 GiB (80%)
Writing library : (dvd5: Oct 27 2015)

Audio
ID : 189 (0xBD)-160 (0xA0)
Format : PCM
Format settings, Endianness : Big
Format settings, Sign : Signed
Muxing mode : DVD-Video
Duration : 23mn 24s
Bit rate mode : Constant
Bit rate : 1 536 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Bit depth : 16 bits
Stream size : 257 MiB (18%)

[poisondeathray]

Recently I was given a video file in mpg2 quality and I rather suspect it's a youtube download "upgraded" to mpg2.
Is there any way to detect this? I mean other than purely visibly, does it leave any telltale traces? Any useful answers will be very much appreciated.

There won't be anything from mediainfo that can tell you. Only by visual examination and comparison , and even that isn't necessarily definitive. Only if the YT version had something specific, some specific artifact or marking could you be fairly certain

[PuzZLeR]

Yes, MediaInfo will tell you nothing regarding the file's lineage. It will only take the file at face value, as an MPEG-2 file. Period.

Only by visual examination can you tell (if so).

Do you see the suspected video on YouTube?

If so, some things you can try.

Look for certain clues, particularly an artifact, as poisondeathray mentioned. As an example, plagerism cases in court were won by proving a mistake from the original was repeated in the copy.

Also, MPEG-2 has its own more-or-less unique set of encoding artifacts, particularly at lower bitrates, so look for certain macroblocking, DCT noise, mosquito noise, etc, ON TOP of what's on the YouTube version.

If you don't know what those artifacts are, you can download the video from YouTube, and encode it with an MPEG-2 encoder to the same bitrate, and cropping, and inspect it, and see how close it looks to the file you got.

And if it was resized, allegedly from a YT file, you can see such resizing artifacts as well.

[Spiny Norman]

Thanks, that's what I was afraid of. The problem is that artefacts are not that frequent anymore now that bitrate and codecs are really good. I'll have to comb through a bit.