I want to transcode an existing MP4 file 640x368 to 480x272, to optimize the video file size for iPhone.
The MP4 includes optional Closed Captions (tx3g)
When I transcode the MP4, using HB 0.9.4, the Captions are not copied over to the smaller file.
Is there some way I can demux the captions from the 1st MP4 file and mux them into the copied file?
Can Closed Captions be preserved, transcoding MP4 to MP4
Forum rules
An Activity Log is required for support requests. Please read How-to get an activity log? for details on how and why this should be provided.
An Activity Log is required for support requests. Please read How-to get an activity log? for details on how and why this should be provided.
Re: Can Closed Captions be preserved, transcoding MP4 to MP4
Subler should do the trick.
Re: Can Closed Captions be preserved, transcoding MP4 to MP4
Cool! Thanks.
Looks like Subler can bring over, not only the Closed Captions track but also the Chapters track from the previous MP4 file.
Looks like Subler can bring over, not only the Closed Captions track but also the Chapters track from the previous MP4 file.
Re: Can Closed Captions be preserved, transcoding MP4 to MP4
Now I'm wondering if there is a way to get the captions from a .MOV file.
Subler will not open .MOV
Sometimes I edit out commercials using SimpleMovieX, but the only way I can preserve captions after editing is to save as a .MOV file.
If I convert the .MOV to .MP4, the captions get lost and Subler can't open the .MOV.
Anyway to extract captions (tx3g) from an .MOV file?
Subler will not open .MOV
Sometimes I edit out commercials using SimpleMovieX, but the only way I can preserve captions after editing is to save as a .MOV file.
If I convert the .MOV to .MP4, the captions get lost and Subler can't open the .MOV.
Anyway to extract captions (tx3g) from an .MOV file?
Re: Can Closed Captions be preserved, transcoding MP4 to MP4
Subler can import tracks from QuickTime .mov files (though it can't open them directly).iSAWaUFO wrote:Subler will not open .MOV
Re: Can Closed Captions be preserved, transcoding MP4 to MP4
I'm in a bit of a snit. I want to extract captions, as the OP did -- but for the express purpose of converting the .tx3g file to SRT. I don't necessarily need it all done in one shot. I'm happy to extract the specific ttxt track, then convert it using whatever.
I am having trouble figuring out how to do this. Am wading through a number of command-line mp4 manipulation utilities, as well as Subler, and am stymied. Take a look at this:
What I'm seeing is a failure by this particular utility (MP4Box) to recognize the raw track 4 data as a 3GPP timed text file. Now, Subler lets me view the track, but not export it as a raw track. Any idea why I'm having trouble extracting the ttxt as a recognizable 3Gpp ttxt file?
I am having trouble figuring out how to do this. Am wading through a number of command-line mp4 manipulation utilities, as well as Subler, and am stymied. Take a look at this:
Code: Select all
% mp4info MOVIE_DISC_1.m4v
mp4info version 1.6
MOVIE_DISC_1.m4v:
Track Type Info
1 video H264 High@3, 456.230 secs, 5824 kbps, 720x480 @ 23.968174 fps
2 audio MPEG-4 AAC LC, 456.234 secs, 164 kbps, 48000 Hz
3 audio ac-3, 456.224 secs, 192 kbps, 48000 Hz
4 sbtl
Tool: HandBrake svn3154 2010030701
% MP4Box -version
MP4Box - GPAC version 0.4.5 (build 33)
GPAC Copyright: (c) Jean Le Feuvre 2000-2005
(c) ENST 2005-200X
% MP4Box -srt 4 MOVIE_DISC_1.m4v
Track ID 4 is not a 3GPP text track
% MP4Box -raw 4 MOVIE_DISC_1.m4v
Extracting '' Track (type 'sbtl') - Compressor Unknown
% file *tx3g
MOVIE_DISC_1_track4.tx3g: data
% MP4Box -srt *tx3g
Unknown input file type
Error importing MOVIE_DISC_1_track4.tx3g: End Of Stream / File
Re: Can Closed Captions be preserved, transcoding MP4 to MP4
Well, I figured it out: older versions of MP4Box didn't recognize the 'sbtl' handler type, only 'text'. 0.4.6 (CVS) does.