Subtitling on the Mac
My first (and only project so far) was quite the learning experience. I'm not doing anything tricky or advanced like video editing, special effects, or the like--I was just putting together subtitles. As with anything else, though, there was a substantial edumacational curve.
So here's what I found, and I hope this spares others from wasting time and energy:
*Jubler simply kicks ass for the creation of subtitles. Specify times, down to the millisecond, when you wanted a subtitle to start, and the corresponding video image will appear. As you type your subtitles, they appear on the still image. Adjusting the subtitle duration, start and end times is a cinch. Can export subtitles to multiple file types, including .ssa and .ass.
*I really wanted to like Avidemux. It's available on multiple platforms; it purportedly allows the addition of subtitle files; and it's friggin' free.
But there are some issues:
Avidemux 2.5.4 (the latest version) won't load .ass subtitles files. In fact, it won't load any subtitle files at all. So I used 2.5.3, which loads more basic, less customizable .srt files.
2.5.3 doesn't offer enough options for subtitle positioning. If only .ass files could be used. . . .
Also, the last line of subtitles was dropped. Solution: create one last subtitle that was blank; then the penultimate subtitles appear.
I could live with those issues. But the audio/video decoupling problems were insurmountable.
First of all, because the source file was an H.264 encoding with B-frames, the program tells you outright that there will be a loss of frame rate accuracy. OK. The program then allows you to rebuild the frames. This always resulted in a crash.
I tried rebuilding the audio VBR map. That didn't work, either.
Ultimately, every exported video file contained A/V dyssynchrony, which worsened (i.e., lengthened) as the movie progressed. By the end of the 97-minute movie, the audio and visuals were divorced by four seconds--unacceptable. And using a fixed temporal offset for the audio (e.g., 500 milliseconds) wouldn't fix the problem, because the dyssynchrony was constantly lengthening.
*Next: Submerge by Bitfield. Platform: Mac only. Limitations: couldn't specify font size by point--can only specify small, med, large, XL. Not perfect, but I can live with those options. Subtitle positioning was a bit more precise than Avidemux: one can specify percentage of screen size by which titles can be vertically offset.
Although Submerge can accept .ass files, it won't do all the neat things an .ass file specifies, such as putting some subtitles at the top of the screen, others at the bottom. Okay dokay--not ideal, but that limitation doesn't exactly constitute epic human suffering; I'll just have all my subtitles on the bottom, which ultimately might be easier for the audience.
Submerge also had trouble interpreting m-dashes. Funny strings of characters appeared instead. So I converted them to n-dashes, i.e., hyphens. Again, not ideal, but the compromise isn't exactly fatal.
Some attempts to export movie + burned-in subtitles via Submerge resulted in blank video the first 5 min, 7 seconds. You could still hear the audio, but the screen was the color of a styrofoam storm for that duration.
Finally got a decent encoding via H.264, but even at high bit rates, there was a slight loss of grain and softening of edges. Also, the exported video was a bit brighter than the source material. However, these difference are almost imperceptible; you really have to do side-by-side still image comparisons to tell the difference.
Submerge finally did the job, so I'll be sending them my $9. One bit of warning: an encoding job that should have taken just a couple of hours (I like the Handbrake rule: an mp4 encode should take about as long as the movie length; maybe a little more for H.264 jobs.) took about two days! Some of the non-H.264 encodes took about a day or so for a 97-minute movie.
Shouldn't the program have tapped the video card's H.264 capabilities to speed up the job? My guess is that the program encodes entirely independently of the video card. There is an option to attach an Elgato Turbo H.264 thingamabob to speed things up, but I have no experience with that dongle, so I can't say how much of a speed boost one can expect.
Last edited by ssj; 04-19-2011 at 02:31 AM.
Subtitles are becoming more sophisticated. Just saw the BBC series HUMAN PLANET and FAST FIVE (a friend dragged me along, I swear), and their subtitles are often displayed with motion, are located in various places across the screen, and sometimes appear letter by letter, as if being typed in real time.
These subtitle display styles are definitely more visually interesting than the static style of yesteryear. On the other hand, it seems that these flashy subs are more suitable for movies that aren't sub-heavy; both of the aforementioned titles display subs only on occasion.
For sub-heavy movies, say, a foreign flick with lots of dialogue, going overboard with neato subs probably won't be a good idea.
Still, I expect it'll be a matter of time before subtitling software (especially freeware) starts to incorporate options for funky sub display.
Last edited by ssj; 05-18-2011 at 10:48 PM.
Nice posts. These things are just a pain to do on OSX or pretty much any *NIX-based OS. It doesn't really help that the tried and true options available for Linux (like AviDemux) often are clumsily ported to OSX. There's nothing wrong with the programme itself, just the OSX version. (Same goes for a lot of other video software tools, like the fact that the only real ffmpeg GUI front-end is the antiquated FfmpegX, last updated aeons ago.) The open source video enthusiast is still on Windows, sadly. Even Linux, usually superior in all things open source, sucks in this department.
This already exists - on Windows. Fire up a VirtualBox installation of XP and try AegiSub. (EDIT: There's actually an alpha release of AegiSub for OSX now - good news! I might try that myself later on.)
Originally Posted by ssj
AegiSub--sounds interesting, theslime. I'll look into it.
Thanks for the heads-up.
aegisub looks great as a subtitle editor.
i'm hoping to tap the collective brainpower here for some direction for exporting video + finished subtitles, via free or low-cost software. don't mind learning about either windows or mac options. (won't be done with my current project for a few months, but i'd like to plan ahead.)
the problem with bitfield's submerge: all the effort i put into specific typesetting goes out the window. my file contains some text in italics, others in smaller font. submerge, however, will present all text with or without italics, and all text the same size. my crouching tiger project is sub-heavy (i estimate the finished deal will contain over 500 sub entries), so having the subs come out just the way i want is mission-critical.
i used submerge for the star wars grindhouse hack (a tip o' the hat again to TMBTM), and it worked out well because there was no need to change font sizes, and the star jedi font just doesn't come in italicized flavors anyway. now my project requires more sophisticated software.
thanks in advance for any tips/suggestions.
btw, avidemux still isn't up to the task. tested it out again last night.
mp4tools is doing an awesome job so far of mixing subs with video+audio.
a few snags: special characters, including the umlaut (as in keyser söze) and the not-so-special m-dash, come out funky. when i had two lines from different characters on the screen at the same time, i would use m-dashes in front of each line; they looked fine in jubler. but during mp4tools' encoding, the m-dashes would come out as gibberish, so i replaced them with regular hyphens --> problem solved. as for the umlaut, all i had to do was drop it and use a regular "o".
so these problems aren't deal breakers at all. the video quality is great. no a/v sync issues.
one thing i haven't tested yet: italics.
if the italics come out nicely, i'll use mp4tools for the final encoding of crouching dragon, at which time i'll also register my copy for, what is it, $4.95? that's a friggin' bargain.
all right, mp4tools is great except for mixing italicized and standard text--it can't do it. neither can submerge.
does final cut pro or final cut express handle .ass files properly? if not, will either program load .srt files properly and allow me to change some text to italics within the same line?
i haven't tried the latest build of avidemux, but that thing crashes like a drunk teenager.
if anybody has experience on these matters, i'm all ears. . . or eyes, as it were. thanks in advance.