Max file size with 140 MBits/second Long GOP
 

Even with Sandisk Extreme Pro 90 MByte/second flash cards, the Nanoflash uses only the maximum file size for Long GOP MPEG2 at 140 MBits/second. Is this something that will disappear with the detection of faster flash cards, or is the Nanoflash processor maxed out ?

Dear Gints,

As I understand your question, you are asking if we can increase the maximum file size from around 3.5 GB to something higher, for when you are using 140 Mbps per second.

We may be able to increase this some.

We have allowed ourselves a little extra room, for safety reasons, due to all of the work we have to do when we reach the "maximum file size".

We may be able to increase this closer to 4.0GB.

Dan, I'm interested in using a smaller file sizes overall, even at higher bitrates. Your previous posts and Nanoflash FAQ indicate that it is difficult for the Nanoflash to keep up with file creation with at higher bitrates.

Dear Gints,

This gets complicated.

At lower bit rates, we can create smaller files, via the "Maximum File Size" parameter in the menu system.

When we reach this threshold, when the file is at the specified Maximum File Size, we open a new file, start writing to the new file, then, while all of this is happening, go back and close the previous file, and write out an index to every single frame in the previous file.

In simple language, we are very busy.

With higher bit rates, especially the very high bit rates, the nanoFlash is very busy.

We have to guarantee that all of this happens before the next file needs to be closed.

We just have to stay ahead of the game.

But, of course, there may be room for improvement in what we are doing.

Interestingly, even the Sony EX's own files (35mbps, 420) are written onto SxS in some 3.6GB chunks - quite a bit lower than the FAT32 size limit.