Hardsubbing in VDM with VobSub Leads to Character Problems

[adalect]

Hi guys,


I am currently re-encoding some files with hardsubs, since I need maximum compatibility for my DivX player. My original files is a MKV, and I am in the process of converting it into an AVI. If anybody wants some context in how I re-encode, I use a AVISynth Script with VirtualDubMod.

At the same time, I also use VirtualDubMod to hardsub the subtitles. I have installed VobSub, and use its TextSub filter that it installed in VirtualDubMod to do the job.

My problem is that certain fonts do not display or covert properly after I finish re-encoding.

For example, this is a picture of the original file:



The word circled in red is of interest here.


Now here is a picture of the subtitle file:



The word circled in red seems to render fine in both the video version and the subtitle file on my computer.


But after I convert the file through VirtualDubMod, and add the subtitles through VobSub's TextSub filter (in VDM), I get this:



Notice that the converted result converts the text in an ill manner.



Can anybody help me here and tell me what has happened? I suspect the problem is either in VirtualDubMod or VobSub, but don't know where to start. Any tips would be nice.

[Ai Haibara]

Make sure the font you're using to hardsub can actually handle that character. If the MKV you're using has fonts included for the subtitles, you might try installing them. (I can't remember whether or not you can get away with having them in the current directory as the videos when you're hardsubbing.)

Also, if you haven't already tried it, you might update VSFilter (copying it to VirtualDub's plugins) to the latest version.

[manono]

And why aren't you using the textsub filter in your AviSynth script? It'll save an unnecessary colorspace conversion and encode faster.

[adalect]

Make sure the font you're using to hardsub can actually handle that character... Also, if you haven't already tried it, you might update VSFilter (copying it to VirtualDub's plugins) to the latest version.

Will definitely look into and update.

And why aren't you using the textsub filter in your AviSynth script? It'll save an unnecessary colorspace conversion and encode faster.

The encode faster part I believe. I'll look into the syntax in a bit and try it out. But as for the colorspace conversion thing, can you explain in more depth as to what you mean. I want to learn how this works as I go, and am curious by what you mean.

[adalect]

Ummm... a problem guys. I don't know what happened exactly, but now the AVISynth script I used doesn't work anymore. It pops out with an error. Here's the basic script (I'll add in the modifications you guys suggested as soon as this works again):

Directshowsource("FileName-Here.mkv", fps=23.810, convertfps=true)

The FileName-Here is the filename...

And here's what MediaInfo says about the file:

General
Complete name                    : L:\ <A bunch of Subfolders> \FileName-Here.mkv
Format                           : Matroska
File size                        : 149 MiB
Duration                         : 23mn 50s
Overall bit rate                 : 875 Kbps
Encoded date                     : UTC 2011-04-05 18:38:03
Writing application              : mkvmerge v4.0.0 ('The Stars were mine') built on Jun  6 2010 16:18:42
Writing library                  : libebml v1.0.0 + libmatroska v1.0.0
Cover                            : Yes

Video
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : High@L3.1
Format settings, CABAC           : Yes
Format settings, ReFrames        : 8 frames
Codec ID                         : V_MPEG4/ISO/AVC
Duration                         : 23mn 38s
Nominal bit rate                 : 750 Kbps
Width                            : 848 pixels
Height                           : 480 pixels
Display aspect ratio             : 16/9
Frame rate                       : 23.810 fps
Original frame rate              : 24.000 fps
Colorimetry                      : 4:2:0
Scan type                        : Progressive
Bits/(Pixel*Frame)               : 0.077
Writing library                  : x264 core 98 r1629 2e81ce1
Encoding settings                : cabac=1 / ref=8 / deblock=1:0:0 / analyse=0x3:0x133 / me=umh / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=-2 / threads=1 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / constrained_intra=0 / bframes=6 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / weightp=0 / keyint=240 / keyint_min=24 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=2pass / mbtree=1 / bitrate=750 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=1927 / vbv_bufsize=1927 / ip_ratio=1.40 / aq=1:0.50 / nal_hrd=none

Audio
Format                           : AAC
Format/Info                      : Advanced Audio Codec
Format version                   : Version 4
Format profile                   : LC
Format settings, SBR             : No
Codec ID                         : A_AAC
Duration                         : 23mn 50s
Channel(s)                       : 2 channels
Channel positions                : L R
Sampling rate                    : 44.1 KHz
Resolution                       : 16 bits

Text
Format                           : ASS
Codec ID                         : S_TEXT/ASS
Codec ID/Info                    : Advanced Sub Station Alpha

I try opening the AVISynth script and get this error:




What frustrates me is that this I used this exact same script to make a converted file I showed you guys a couple of hours ago. What happened?

[manono]

But as for the colorspace conversion thing, can you explain in more depth as to what you mean.

When you use VDub(Mod) filters, you have to use 'Full Processing'. This forces a colorspace conversion from YV12 (which I believe your 'source' is) to RGB and then back again. This slightly degrades the final quality as well as slowing the encode. Using the Textsub filter in the AviSynth script allows you to use 'FastRecompress' and it stays in YV12 all the way, a much better solution.

[adalect]

Thanks for the explanation manono. Very clear, very concise, and easy to understand. Much appreciated.

Now... can anybody guide me with my DirectShowSource error?

[El Heggunte]

Make sure both the AVS file and the MKV file are in the same folder ;

[adalect]

Make sure both the AVS file and the MKV file are in the same folder ;

Both files are in the same folder. Judging by the wording of the error box, it seems AVISynth can find the file, but DirectShowSource doesn't seem to know how to react. I am not too sure as to what to do to fix DirectShowSource.

[manono]

I am not too sure as to what to do to fix DirectShowSource.

Don't use it. Use FFMPEGSource instead:

http://code.google.com/p/ffmpegsource/

http://ffmpegsource.googlecode.com/svn/trunk/doc/ffms2-avisynth.html

[El Heggunte]

^
^ Well, the fact is, Avisynth not always builds (or attempts to build) a DirectShow graph in the same way as MPC-HC for example (not to mention Graphstudio and the infamous Windows Media Player). As a last resort, you can always (try to) build a functional graph manually in Graphstudio, save it, and apply DirectShow Source() on it. Besides, thanks to the 'convertfps' option, you can choose a framerate value more convenient than "23.810fps"

Even though FFMpegSource is very-good, I simply don't like it very much Especially because in certain cases it has to use the annoying Haali Media Splitter. I prefer both LAV Splitter and AV Splitter to HMS, which is still "most useful" only to the «animé "releasers"», apparently.

[adalect]

I did another batch of Googling, and many people mentioned that codecs may be a problem. I found that DirectShowSource failed to work with MKV files (but not AVI files), so I uninstalled and reinstalled the Haali Media Splitter package I had. Now it works! Thanks for the help so far guys.

Also, if you haven't already tried it, you might update VSFilter (copying it to VirtualDub's plugins) to the latest version.

Trying this at the moment, and it seems to work. I'll update if something breaks, but otherwise it should be fine now. Thanks!

Use FFMPEGSource instead...

Just curious, what is the biggest difference between FFMPEGSource and DirectShowSource? I read something about support for variable frame rates, but then I also read something about having to index files if you use FFMPEGSource. Can you give me the skinny about this?

[manono]

I never use DirectShowSource if I can possibly avoid it. For one thing, it's often not frame-accurate and seeking can be screwy. Yes, FFMPEGSource indexes the file, the way DGIndex indexes an MPG of some sort. But that is, in my opinion, a good thing, and it doesn't take long at all. I use it for everything but DVD/MPEGs (which I index first using DGIndex, together with MPEG2Source), and most AVIs (for which AviSource is usually used).