MP4 (H264) hangs in MPC-HC

[madk]

Hi all...

I recently encoded six videos in MP4 using HandBrake with the x264 codec. I used the same video settings for all the files because I wanted to join them afterwards (and I used passthru for the audio). So I then joined them with avidemux without re-encoding because I'm pretty sure HandBrake can't do it. Now the problem is: if I play the file in MPC-HC, there are certain points in the video where it will hang, although the audio will keep playing just fine. I can skip forward a little and the video will resume playing although whenever it reaches a "problematic" point, it'll hang again. It always happens at the exact same times (i.e. 1:37, 2:25, etc.) I'm not having that problem if I play each file individually so it only happens with the merged file. I should also mention that VLC Media Player will play both the individual files or the merged file just fine.

Any ideas?
Thanks!

[El Heggunte]

Apparently the MP4 segments were joined improperly by Avidemux
( which is well-known for sucking too much ).

VLC is designed to deal with b0rked files, so it normally doesn't let their problems appear.

[madk]

Thanks for pointing this out! Any ideas as to what other program I could use to join them?

[poisondeathray]

you can try mymp4boxgui to append

it would have been better if you joined them before encoding, because using the same settings doesn't necessarily ensure a successful join

[madk]

But isn't this impossible with HandBrake? Or maybe should I have used another program to encode them?

[poisondeathray]

Yes, it's not possible in handbrake

Encoding it as 1 video will ensure the joining is seamless . Joining videos after they are encoded isn't always that simple, prone to glitches

I would join the original files with an avisynth script, then you can use some GUI that accepts avs scripts eg. ripbot, megui, xvid4psp, staxrip,... many others...etc...

But it still might be worth giving mymp4boxgui a shot (This way you don't have to waste time on encoding)

[madk]

Actually, the first video was an avi (XviD) and the other five were MP4 (H264/x264) so joining them all before encoding wasn't an option. So either way I would have had to join them after encoding, unless I had used something like TMPGEnc Xpress that can take any videos of any format and encode them all into one single file, although TMPGEnc Xpress doesn't support x264 (unless there's something I don't know)

[poisondeathray]

Actually, the first video was an avi (XviD) and the other five were MP4 (H264/x264) so joining them all before encoding wasn't an option. So either way I would have had to join them after encoding, unless I had used something like TMPGEnc Xpress that can take any videos of any format and encode them all into one single file, although TMPGEnc Xpress doesn't support x264 (unless there's something I don't know)

That's sort of the point;

Avisynth works in the uncompressed domain , so it doesn't matter if it's xvid or h264 or whatever . Since you were re-encoding anyways, so any concerns about quality loss is moot . (and if you don't re-encode, you're left with uncompressed video - huge). The video are joined in the script, and avisynth acts as a frameserver to whatever encoder you are using . There is no need for big lossless intermediate files either, the script is just a text file a few kb large

You need to match the other properties, such as frame rate, dimensions, etc... but avisynth has many filters so you can adjust footage to match the other in the script

[madk]

Thanks anyway but the video joined with mymp4boxgui loses the audio after the first part. I guess I'll have to re-encode everything...unless I could demux the audio, join the AAC files together and remux it.

[poisondeathray]

Do you still have the original files ?

You can try joining the mp4 files in mkvtoolnix (as mkv) , then re-wrap into mp4

Otherwise I would take the avisynth route (as you can see "joining" videos after encoding isn't as straightforward as it may seem)

[madk]

And that might sound stupid but...how would you re-wrap it into mp4?

[poisondeathray]

And that might sound stupid but...how would you re-wrap it into mp4?

e.g. ffmpeg , avidemux , I think yamb or mymp4box can do it (if not, you can demux then remux)

The important part is if it joins properly or not...

As you can see it can be a crapshoot trying to join files

It's always better to encode it properly in the first place (ie . as 1 video, eg. using avisynth )

[madk]

Yes you're right...I've had my lesson, I guess :P If I had known that initially, that's what I would have done. I guess it's way easier to join avi's encoded with the same settings, same resolution and same codec.
Now I'll have to schedule a few hours to re-encode my mp4's

[madk]

Just thought I'd provide an update...I couldn't figure out how to set up AviSynth to use with Handbrake (which doesn't support AviSynth scripts) so I re-encoded the video with avidemux. avidemux has an "Append" function so I was able to feed it all of my videos before encoding them. I'm not sure if the video quality would've been better in Handbrake but from what I'm seeing right now, the loss of quality engendered by re-encoding is very minimal and the video looks 99% like the original. Either way, it was a heck of a lot easier than setting up a frame server. The resulting file is one seamless video and it plays perfectly in both VLC and MPC-HC with no audio delay, which I was a little worried about because I didn't re-encode the audio. So it took me some 8-10 hours to do it but I didn't really have any other choice if I wanted a playable video file. So all's well that ends well

Thanks again for your help!