cannot extract some kind specified yaffs2 img

[GoogleCodeExporter]

i am doing some stuff extracting image file from a phone.
as i entered adb shell and use mount to find out the file system of /system 
partition is yaffs2   . so i tryed dd if=/dev/mtd/mtd4 of=/sdcard/system.img 
and cat /dev/mtd/mtd4 > /sdcard/system.img and pull to my computer(running 
fedora linux 16) .

but i can not extract the two image files .unyass2 output image file size is 
not a miltiple of 20048+32 (or other number i dont remember)

some says this file system built in my phone is modified base on yaffs2 file 
system.i wonder how to extract these image files.

Original issue reported on code.google.com by zhuhaiya...@gmail.com on 15 Feb 2012 at 8:20

• Merged into: #16

[GoogleCodeExporter]

At this moment, unyaffs2 still cannot extract the image dumped directly from 
the device (see README).

Original comment by luenyung...@gmail.com on 21 Feb 2012 at 4:45

[GoogleCodeExporter]

Original comment by penguin.lin on 10 Mar 2012 at 2:45

• Changed state: Duplicate