Problem with encoding MPEG-TS with variable GOP

[Insurgent]

Hi. I'm not an expert on video coding, so please let me know if I get things wrong.

I record a lot of TV shows from my satellite box, and the output is always in MPEG-TS. When I check the MediaInfo, I find that the format setting for GOP (group of pictures) is "variable". What I think I understand from this is although the framerate is displayed as 25 FPS, some parts seem to play as 60 FPS. This is where my problem culminates. I want to encode the video from MPEG to H.264 while retaining a variable framerate. However, it's pretty much impossible with HandBrake because when I set the FPS options to 25 and peak framerate, it always outputs a constant framerate no matter what. Is there a way other than HandBrake to deal with this?

By the way, here is part of the MediaInfo for reference:

Video
ID                             : 1304 (0x518)
Menu ID                        : 10304 (0x2840)
Format                         : MPEG Video
Format version                 : Version 2
Format profile                 : Main@Main
Format settings, BVOP          : Yes
Format settings, Matrix        : Custom
Format settings, GOP           : Variable
Format settings, picture struc : Frame
Codec ID                       : 2
Duration                       : 1 h 55 min
Bit rate mode                  : Variable
Bit rate                       : 2 319 kb/s
Maximum bit rate               : 2 919 kb/s
Width                          : 720 pixels
Height                         : 576 pixels
Display aspect ratio           : 4:3
Active Format Description      : Full frame 16:9 image
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)             : 0.224
Time code of first frame       : 16:04:01:21
Time code source               : Group of pictures header
GOP, Open/Closed               : Open
Stream size                    : 1.88 GiB (81%)

[pandy]

GOP is something else than FPS - AFAIK MPEG-2/H.262 do not support variable framerate so everything seem to be OK at least for me... variable GOP is one of many ways to improve coding efficiency - same approach is used in H.264 world...

[Cornucopia]

Here is an example of a sort-of constant GOP format:
IBPIBPIBPIBPIBPIBP
and another sort-of constant (common one):
IBBPBBPBBPBBPBBPIBBPBBPBBPBBP
and one even more constant:
IIIIIIIIIIIIIIIIIIIIIII

Here is an example of a wildly variable GOP format:
IIIIIBPIBBPBBPIIBPIPPIBBPBBPBBPIIBBBBBPIPIBIP

(it's possible that as far as mediainfo is concerned, those 1st 2 examples, though repetitive, could also be considered variable. the 3rd is truly constant)
Note that it is likely that all of the above frames are of the same duration, aka constant framerate.

Look at the MediaInfo report again:
Format settings, GOP : Variable
Bitrate mode: Variable
Framerate: 25.000 FPS (aka constant)

Variable Frame rate is almost unheard of in broadcast. (personally, I avoid it like the plague, except when necessity arises, like with cellphone cameras)
Variable Bitrate is common in many places, including broadcast.
Variable GOP format depends on the program material, but is common enough in broadcast when you consider the inclusion of interstitials, ads, etc.


Scott

[netmask56]

Run one of your TS files through TS-Doctor or VideoRedo and see what if any errors that are thrown up.

[Insurgent]

Run one of your TS files through TS-Doctor or VideoRedo and see what if any errors that are thrown up.

I just tried out VideoReDo, encoded one of my files to AVC and set a constant framerate to 59.940. The results were just what I expected. Thanks a ton.