HydrogenAudio

Lossy Audio Compression => Ogg Vorbis => Ogg Vorbis - Tech => Topic started by: sizeak on 2011-06-08 13:02:49

Title: Help: Editing compressed Ogg Vorbis files
Post by: sizeak on 2011-06-08 13:02:49
Hello,

I'm working on a project that requires me to be able to edit Ogg Vorbis files without decoding them. I have this nearly working by decoding the input stream far enough to get Ogg packets, then using those to build new pages for writing to an output file. Packets which are in the range that I'd like to drop are simply not put into the output pages. I also adjust the packetno of packets after the cut so there isn't a huge gap in them; I'm not sure if it's necessary but it keeps things tidy.

However I think I'm missing something, possibly something else that I need to update and haven't. When I try and play the edited file in VLC, it seems to skip to roughly 2 mins into the file, even though the edit occurred within the first 20 seconds of audio and the decoder example from libvorbis produces an unreadable wav file when used with a file edited like this. Audacity on the other hand can read the edited file fine and can also produce a perfectly valid wav file from it.

So while I think I'm close, there is something which is missing thats probably staring me in the face and I'm not realising it. Any help would be appreciated thanks,

Sizeak
Title: Help: Editing compressed Ogg Vorbis files
Post by: sizeak on 2011-06-08 15:46:34
I think I've solved this myself with the help of the vcut source code
Title: Help: Editing compressed Ogg Vorbis files
Post by: kuann on 2012-05-24 02:31:26
Hi, sizeak,

I'm working on it recently, can you give some hints about how you do it? Thanks.