Petition for Samsung NX1 hack

[ChristieEnglish]

Using the hack to remove the 30 minute record limit will cause the NX1/NX500 di-camera-app to crash when the output file reaches 34.67GB.

The crash can be replicated on both NX1 and NX500 recording in 1080p Pro mode at 24 fps.  Both cameras crash leaving an unusable 34.67GB MP4 file.

The crash will leave you with a 34.67GB truncated MP4 video file that is not playable.  Does anyone know how to recover the faulty MP4 file?

Attached is the crash log.

20160319_094727_a9_crash.info

[EOS_Lurker]

Has anyone tried using kexec in nx_cs.adj to get Tizen to boot from an OS partition the SD card?  This might allow us to mod the OS on the SD while leaving the embedded copy alone, reducing brick-risk.

[ReinisK]

7 hours ago, ChristieEnglish said:

Using the hack to remove the 30 minute record limit will cause the NX1/NX500 di-camera-app to crash when the output file reaches 34.67GB.

The crash can be replicated on both NX1 and NX500 recording in 1080p Pro mode at 24 fps.  Both cameras crash leaving an unusable 34.67GB MP4 file.

The crash will leave you with a 34.67GB truncated MP4 video file that is not playable.  Does anyone know how to recover the faulty MP4 file?

Attached is the crash log.

20160319_094727_a9_crash.info

Try this tool - http://www.videohelp.com/software/Video-Repair-Tool

You need to input another file, which is not corrupted, of the same camera and then input the corrupted file.

It has worked for me with Gopro and Canon dslr files, I don't know, what about h265, but I assume that if your PC has the codec installed, it should work fine.

[sandro]

hasn't someone tried to solve this corrupted file thing disabling power saving mode in the dev menu? maybe I've dreamed about it

[RieGo]

52 minutes ago, sandro said:

hasn't someone tried to solve this corrupted file thing disabling power saving mode in the dev menu? maybe I've dreamed about it

afaik someone (i think it was otto?) found the problem, which is a memory leak. he also provided a possible fix that nobody tried so far. disabling power saving mode didn't work.

i just can't seem to find that post anymore... it was either here or on dpreview. i'll report back once i found it.

 

update: there it is: 

 

[sandro]

ok thanks... anyway don't be offended but isn't time limit removal the last of our concerns right now? I can't find a reason to use such a powerful cinematic tool to record for such a long time

I wonder why internal storage is so slow...what if we try to enable swapping on the sd card? with fastest cards it shouldn't be a problem I guess

[Otto K]

The issue is not with speed of SD card, it's just that swapon command complains about the file structure if it's on SD card (don't know why, it's works fine on my laptop with Linux). Either way, speed of swap is not important as it has to write around 500MB in over an hour. 

[Jorgen Gerstel]

Yesterday filmed in 4K the korfball Play Off - Sports Event + 720p livestream to youtube with the "DEV" hacks to disable 30 mins limit and lens check.

Camera NX1 proofs to be stable, even in stress conditions of the sports event! 

• Camera: NX1
• Lens: Canon Broadcast J17ex7.7B4
• Record: 2160  25p on Komputerbay SD card
• Video out: 1080P for Youtube livestream

Great work and many thanks :-)

[ChristieEnglish]

I tried a couple of the recovery tools that has the user specifying a reference good video file and a corrupted video file and they do not work.  I believe those tools are specific to H264 codec.

It looks like there is an untrunc project on github to recover Samsung video files.   The untrunc project is a good start, but would need to be modified to work with corrupted hevc files. Looking at the source code it looks like the track.cpp has reference to avc1 codec.  We would need to refer to hvc1 instead.  

 

Untrunc project:

https://github.com/ponchio/untrunc

 

The Untrunc author's web page with some info about his approach and why he wrote the software:

http://vcg.isti.cnr.it/~ponchio/untrunc.php

 

From StackOverflow:

http://stackoverflow.com/questions/32697608/where-can-i-find-hevc-h-265-specs

the hvc1/hev1 box is parsed exactly the same way as the avc1/2/3/4 boxes. The hvcC box though is parsed slightly differently than the avcC box. For parsing that one, you could look at how this is parsed in some open source projects, such as ffmpeg or vlc.

[SMGJohn]

13 hours ago, ChristieEnglish said:

Using the hack to remove the 30 minute record limit will cause the NX1/NX500 di-camera-app to crash when the output file reaches 34.67GB.

The crash can be replicated on both NX1 and NX500 recording in 1080p Pro mode at 24 fps.  Both cameras crash leaving an unusable 34.67GB MP4 file.

The crash will leave you with a 34.67GB truncated MP4 video file that is not playable.  Does anyone know how to recover the faulty MP4 file?

Attached is the crash log.

20160319_094727_a9_crash.info

I recommend not to overexceed the time of 70 minutes because on me it crashes everytime exactly on 78 minutes recording time and leaves a 43GB useless file which is pointless to eventry to recover because its so massive and HEVC is a pain in the "#((&(¤% to work with when you do not have HEVC hardware encoding.

Otto had a potential fix for it, but my Linux/Android skills are less than satisfactory.

 

[ChristieEnglish]

Recovering a truncated HEVC MP4 file would not require re-encoding since the data is already encoded. I would require finalizing the file and making sure all the MP4 box atoms are correct.

[SMGJohn]

16 minutes ago, ChristieEnglish said:

Recovering a truncated HEVC MP4 file would not require re-encoding since the data is already encoded. I would require finalizing the file and making sure all the MP4 box atoms are correct.

I know, but its a huge file we are talking about, something oughta read it and that requires system resources. There are only a few methods to recover a HEVC from my knowledge and almost every one of them are console driven. And only software which is Untrunc can only be run on a Linux distro so that means you gotta use virtual computer or a different computer with Linux. A truly painful experience, worth it if the file is important I suppose, but its easier if you just stay under the 70 minute mark, you said 34GB file so I suppose it might depend on the SD card used as well.

[ChristieEnglish]

One of the forked untrunc projects has a patch to run it on Mac OSX.  That patch mostly fixes compilation and endian issues on the Mac.

https://github.com/jensp/untrunc/tree/osx_support

 

[vaga]

you could probably get it to run on the camera itself

[ChristieEnglish]

Having a truncated MP4 file recovery utility running on the camera would be really cool.  To avoid complicated menus, the utility when executed could automatically scan the SD card for truncated files and automatically recover them.

[caseywilsondp]

On 3/19/2016 at 7:14 PM, SMGJohn said:

The higher bitrate has definitely seemed to help quite a lot, I also noticed less banding in blue sky with -10 contrast in GammeDR with 1.40 after they increased bitrate, which means banding issue can indeed be fixed with higher bitrate, now imagine what it would look like with 200mbps+ bitrate,

Unfortunately it'll look like this:

colored and punched into problem area:

600+ mbps prores hq recorded on shogun from the nx1

of course that is gamma dr -10 contrast... so about as extreme as you can get, and maybe its usable in cases where you wont have gradients, but as i demonstrated a lot in the "your ideal nx1 settings" thread, increased bitrate will help us with shadows and highlights (we can improve usable DR by 2 stops is my guess), but we need 422 to get us away from banding.

[SMGJohn]

37 minutes ago, caseywilsondp said:

Unfortunately it'll look like this:

colored and punched into problem area:

600+ mbps prores hq recorded on shogun from the nx1

of course that is gamma dr -10 contrast... so about as extreme as you can get, and maybe its usable in cases where you wont have gradients, but as i demonstrated a lot in the "your ideal nx1 settings" thread, increased bitrate will help us with shadows and highlights (we can improve usable DR by 2 stops is my guess), but we need 422 to get us away from banding.

I have used the Shogun myself with the NX1 once on a short film, I did not notice much differences or gains so I just shot without it on difficult shots.

I think the NX1 only spits out the same bitrate its set in the menu out on HDMI, I might be terribly wrong but its what I think based on personal experience with the shogun and the NX1

[Hanriverprod]

9 minutes ago, SMGJohn said:

I have used the Shogun myself with the NX1 once on a short film, I did not notice much differences or gains so I just shot without it on difficult shots.

I think the NX1 only spits out the same bitrate its set in the menu out on HDMI, I might be terribly wrong but its what I think based on personal experience with the shogun and the NX1

 

They say the same thing for using Shogun with Gh4 and a7s. Huge unwieldy files and no discernible improvement in the image. Besides the monitoring benefits it doesn't seem like they really make the image thicker for grading. Seems like a huge price to pay to discover this.

 

[caseywilsondp]

23 minutes ago, Hanriverprod said:

They say the same thing for using Shogun with Gh4 and a7s. Huge unwieldy files and no discernible improvement in the image. Besides the monitoring benefits it doesn't seem like they really make the image thicker for grading. Seems like a huge price to pay to discover this.

 

having used it with the a7s, that's just untrue. 422 8bit with big bitrates gave a hugely malleable image that virtually never banded (and we're talking about using it with slog2, a super flat image). I can't speak for the gh4

also, whats unweildy about prores lt? however, for the nx1, I'm not sure the price is worth the extra bitrate. while people have said its 422 over hdmi on the nx1, i don't see the color improvements i would expect if that were the case.

40 minutes ago, SMGJohn said:

I have used the Shogun myself with the NX1 once on a short film, I did not notice much differences or gains so I just shot without it on difficult shots.

I think the NX1 only spits out the same bitrate its set in the menu out on HDMI, I might be terribly wrong but its what I think based on personal experience with the shogun and the NX1

not being a Samsung engineer i can't say for certain what bitrate is actually being spit out, but it is an improvement over the internal files particularly in shadow detail and virtually eliminating macroblocking. highlight detail is also a little bit improved, but not much. if I didn't already have the shogun I probably wouldn't go out and buy it, but because I own it the little extra improvements are worth the extra weight on my rig.

anyways my post wasn't about the usefulness of the shogun, it's about keeping peoples expectations when it comes to higher bit rates in check.

[Hanriverprod]

9 minutes ago, caseywilsondp said:

having used it with the a7s, that's just untrue. 422 8bit with big bitrates gave a hugely malleable image that virtually never banded (and we're talking about using it with slog2, a super flat image). I can't speak for the gh4

also, whats unweildy about prores lt? however, for the nx1, I'm not sure the price is worth the extra bitrate. while people have said its 422 over hdmi on the nx1, i don't see the color improvements i would expect if that were the case.

not being an engineer i can't say for certain what bitrate is actually being spit out, but it is an improvement over the internal files particularly in shadow detail and virtually eliminating macroblocking. highlight detail is also a little bit improved, but not much. if I didn't already have the shogun I probably wouldn't go out and buy it, but because I own it the little extra improvements are worth the extra weight on my rig.

anyways my post wasn't about the usefulness of the shogun, it's about keeping peoples expectations when it comes to higher bit rates in check.

I'm hoping for 422 or 444 too. I wouldn't even care being abandoned...