[FFmpeg-user] Prores seek to position is slow

[Andrew]

Hi,

I'm trying to use ffmpeg to convert Prores streams to TIFF sequences. 
I'd like to be able to start converting the file part way through, for 
instance a 10 minute file, perhaps only 00:05:00 to 00:06:00.

But no matter the setting of -accurate_seek / -noaccurate_seek it 
appears to take a long time to arrive at the starting position... almost 
as long as just ripping the entire file from the beginning.

On a Mac using an official Prores implementation like Final Cut Pro, 
seeking is immediate. Am I doing something wrong?

Doing:

ffmpeg -y -i input.mov -r 24 -pix_fmt rgb48le -vcodec tiff -ss 00:01:00 
-to 00:01:01 tiff/%06d.tif

Takes almost as long as:

ffmpeg -y -i input.mov -r 24 -pix_fmt rgb48le -vcodec tiff -ss 00:00:00 
-to 00:01:01 tiff/%06d.tif



Thanks,

Andrew