Adding Hard Subs to MKV/MP4
 

Hi, I searched on the forums but couldn’t find a good answer for this... I'm trying to watch HD anime on my Xbox 360, but when converting from MKV to MP4 I loose the embedded subtitles. Is there any way to make the subtitles permanent without re-encoding the video (loosing quality)? I've been using PS3 Video 9 to do my mkv to mp4 converting if that helps any... Thanks!

No. Hard-subbing involves encoding the subtitles themselves into the video, as part of the video. Hence it's impossible to create a hard-sub without re-encoding the video.

I did a quick Google for softsubs and MP4; I didn't see anything explicitly stating that MP4 doesn't support softsubs, but I didn't see any how-to's on it, either. It may be the software that you're using.

edit: based off of some searching for another thread in this forum which asked about converting MKV to MP4, it seems like the process involves re-encoding of the video regardless. Try using a different program, or examining the options to see if it'll allow you to insert a subtitle file. It's easy to get the subtitle file out of an MKV file, if that's what is necessary.

MP4 supports ttxt softsubs, which is xml madness. If the softsubs are in ASS format, extract them from the MKV using mkvtoolnix and mkvextractGUI. Then download Aegisub or SSATool and convert them to SRT (note: in this process you are losing all the styles, you will get only a plain ugly subtitle). Then download mp4box and a GUI for it, like YAMB. And there it offers to convert an SRT subtitle to the ttxt format in one of the menus. And you should be able to mux that into the MP4 file. (Note: this process is just from the top of my head, I haven't tried it myself before whether it actually works, it's just theoretical.)

If you want to know how to re-encode just say so please. That way you won't be losing the style, but will lose some of the original quality.

Well I need to re-encode, I just didn’t want to do it more than once. I would appreciate it if you could tell me a better way to go about this than using PS3 Video Encoder... it was just the only program I could get working for me. For instance if you know of a method of encoding that will hardcode the subs and produce a MP4 file at once, that would be the best. I'm going to try muxing in softsubs with the MP4, but I don’t know if the Xbox 360 supports that... Thanks!

I don't think any hardware devices currently support TTXT subtitles really. You can play them on your PC at least :P.

As for the "better way to encode" of course there is. Simplest would be to use AviSynth. Depending if you want H.264 or not, feed the avs to x264 which can immediately give you MP4 output, or just encode in VirtualDub to Xvid/DivX and mux to MP4 with mp4box. You'll need to read up at least a bit on how to use AviSynth most likely, you use VSFilter to hardsub the subtitles in the avs.

Actually, if PS3 Video 9 is related to PSP Video 9, then you can load the AVS (AviSynth) file directly in it. That may not result in the best quality (depending on the setting), but does guarantee the resulting file is playable on PS3 (or Xbox 360 with latest update I suppose).

I used this technique to encode some fansubs (including ones in MKV format with soft-subtitles) to PSP format so that I could watch them on the go.

Use MKVExtractGUI to extract the subtitle file, then use a AVS script like this one (fix all the paths and filenames!):

Thanks for the reply, sorry I couldnt write back sooner... have had some family emergencies. I've tried to use your method but after several minutes I get an error saying ffmpeg needs to close. I dont know much about avs scripts, so maybe i'm doing something wrong. I would really appreciate it if somone could point me towards some tutorials for using alternate encoders with avs scripts. This is the script I made, just in case someone can spot something wrong... Thanks!

LoadPlugin("C:\Program Files\K-Lite Codec Pack\filters\vsfilter.dll")
DirectShowSource("D:\[KAA]_Ghost_in_the_Shell_2_INNOCENCE_(H264.AC3_6.1ch)[Blu-Ray_rip]\Ghost_in_the_Shell_2_INNOCENCE.DVD(H264.AC3_6.1ch )(1920x1040)[KAA][D5EBB932].mkv")
TextSub("D:\[KAA]_Ghost_in_the_Shell_2_INNOCENCE_(H264.AC3_6.1ch)[Blu-Ray_rip]\track3.ass")

I'm not sure if I'm right but in the code you put
TextSub("D:\[KAA]_Ghost_in_the_Shell_2_INNOCENCE_(H264.AC3_6.1ch)[Blu-Ray_rip]\track3.ass")
but might it be
TextSub("D:\[KAA]_Ghost_in_the_Shell_2_INNOCENCE_(H264.AC3_6.1ch)[Blu-Ray_rip]_track3.ass")