Wednesday, June 10, 2009

NTFS A Journaling File System

If NTFS is a journaling file system (if you don't know what it is, I suggest you read it up first before continuing) then why do we have to perform such an extensive chkdsk (checkdisk or scandisk) every time the system does not shutdown cleanly (due to a power or system failure)?

A journaling file system should always have their file system in a consistent state. For example, the MFT (Master File Table) should never indicate a cluster as being occupied while it in fact isn't. But so often when we don't cleanly shut Windows (2k or XP for that matter) down, the checkdisk that runs when Windows boots up again will find the exact inconsistency as described above.

Q: So is NTFS a journaling file system?
A: Yes.

Q: Then why is NTFS inconsistent?
A: NTFS is ONLY inconsistent (or unsafe) when an unclean shutdown occurs if you are running Windows 2K or XP. Microsoft for some reason (most likely performance related) chose not to enable the journaling function for non-server version of Windows. Windows Vista, however, enables it by default (I'm assuming Windows 7 does as well).

Q: Should I enable NTFS journals then?
A: It's up to you really, but personally I have a higher preference for the safety of my data, and I can't tell the speed difference between having it enabled / disabled on my hard drives, so it's a definite Yes for me.

Q: How do I enable NTFS journals?
A: Go to command prompt and run the following command for each NTFS partition:
fsutil usn createjournal m=1000 a=100 C:

Q: How do I check if my NTFS partition has journals enabled?
A: Run the following command:
fsutil usn queryjournal C:

Q: Does that mean I don't have to run chkdsk any more?
A: Not really. Just that you don't have to do it every time you fail to shutdown your computer properly. You should still do it occasionally (like defrag).

Q: How do I disable chkdsk on start-up?
A: http://www.raymond.cc/blog/archives/2008/02/23/disable-or-stop-auto-chkdsk-during-windows-startup/

Catalyst 9.6 ATI 4000 HD Series Still Behind NVIDIA For HTPC

ATI is still behind NVIDIA for HTPC even with the latest leaked Catalyst 9.6 - It still fails to decode L5.0 / L5.1 high profile AVC video in DXVA mode (using MPC-HC for example). This means that for HTPC, a NVidia 8600GT / 9400GT would be the better choice over ATI HD 4800 / 4700 / 4600 / 4500 / 4300 series.

If you're looking to build a HTPC, go for NVIDIA.

While ATI heavily promotes its HTPC capabilities, the truth is it is still very far behind NVIDIA.

NVIDIAusers have been enjoying this for about 6 months.

@NVIDIA marketing, you could consider starting a "The way it's meant to be watched" program. Doesn't look like ATI has anything left in them to pose a threat whatsoever.

Tuesday, June 2, 2009

ATI HD Hardware Accelerated DXVA for H.264 AVC L5.0 / L5.1

HOW TO: Get hardware accelerated DXVA playback of HD AVC High Profile L5.0 / L5.1 MKV / MP4 Files on ATI HD Series.

Well, technically speaking, not DXVA, but hardware accelerated playback of L5.0 / L5.1 files nevertheless.

I've recently built a HTPC from an old Pentium 4 HT. I know it has not enough grunt to decode AVC High Profile video, so I bought an ATI 4350 HD in the hope that it'll do all video decoding on its GPU (or UVD).

To my disappointment, I found this (ATI does not support AVC with High Profile above L4.1) after I bought the card. All my encodes are done with L5.1 as my other PC is a Core 2 Duo which has an NVidia 9600GT. For some reason, the NVidia driver is able to support DXVA for AVC High Profile L5.1, so I simply assumed ATI would be the same. Turns out that the maximum the ATI would do is L4.1 (There's a Quantum of Solace trailer encoded at L5 to test here - http://nunnally.ahmygoddess.net/watching-h264-videos-using-dxva/).

Regardless of which decoder I use, my P4 HT simply isn't powerful enough to playback these files (CPU hits 100% all the time and frames drop very frequently).

Luckily for us ATI owners, there is a solution. With PowerDVD9 and Catalyst 9.5, I finally found a combination that would get 1920x1080 HD videos with ref-frames > 4 to play without taxing my CPU. In fact, I was pleasantly surprised when I reran the Quantum of Solace test video -- my CPU remained at 2% utilization!

I recommend the following setup for ATI users:
  • PowerDVD 9 build 1719 ==> Must be this build! Other builds will not work
  • ATI Catalyst 9.5 (non-hotfix version)
  • AC3Filter
  • Haali Media Splitter (to playback MKV files) ==> version 1.9.42.1 (or later)

*** Note1:


Rename .MKV to .MP4 to get PowerDVD to playback MKV files.

*** Note2:

Important
- No other filters (e.g. FFDShow / CoreAVC / Codec Packs) should be installed in your system!


Try it out yourself (you could download the trial version of PowerDVD 9).

MAKE SURE you DO NOT have any other filters installed (for example, CoreAVC or FFDShow which may have a higher merit than PowerDVD's own filter) or PowerDVD will not use its internal H264 decoder. Also, when opening MKV files, PowerDVD will complain that xvidcore.dll could not be found, but will continue playing the video just fine. If you want to suppress the error message, simply download xvidcore.dll and put it in the same folder as the PowerDVD executable (e.g. c:\Program Files\CyberLink\PowerDVD\).

Leave a comment to let me know if it does / doesn't work for you with your card's configuration and OS, for example:
  • HD 4350 PCIe x16 512MB
  • WinXP SP3

*** Update 1:


This clip (the 'Bird Scene' from Planet Earth) is the ultimate L5.1 super high bitrate MKV sample. On my nVidia 9600GT setup with a E7200 CPU @ 3.6GHz, it uses 50% of the CPU (playback using MPC - Home Cinema with driver supporting L5.1 bitstream DXVA). On my Pentium 4 HT (single core CPU) and the HD 4350 setup, I get 25% CPU usage. That is simply mind-boggling! What can we conclude? ATI is A LOT better at decoding H264 streams?

*** Update 2:

I've found that PowerDVD has a problem with H264 encoded files that have been tagged with the wrong IDC. For example, if the file actually contains a high profile L5.1 bitstream but its IDC tag is marked incorrectly (e.g. L4.1), you will get stuttering problems. If that happens, you'll have to change the file's IDC tag back to L5.1 using IDC Multi Changer.

*** Update 3:

While testing my configuration with a ref-frame 12 encode at 1920x800, I found that certain scenes (usually panning slowly) would judder (i.e. a couple of frames get dropped) and they always happen at the exact same time code. I tried remuxing the .mkv file to .ts / .m2ts but to no avail. I also increased the input buffer size to 100000KB from 8192KB in the Haali Media Splitter settings, which also did not help. Having spent a few hours on it, I finally decided to look at PowerDVD's settings itself. Apparently, under Advanced Video Preferences (Right-click Main Screen, click on Configuration, select the Video tab, click Advanced...), there's a group box called Video Quality. I had Normal Mode selected from before when I was using PowerDVD without AVIVO. Setting it to Best Mode solves the problem. GPU and CPU usages remain unchanged at 6-8% and ~12% (DTS is being decoded in software) respectively.

I can only make an educated guess on the reason behind the judder. Video Quality relates to the post processing / de-interlacing / pulldown settings. The judder which I picked up on slow panning scenes are probably due to the lack of pulldown under Normal Mode. When set to Best Mode, pulldown (what is this?) is activated to match the 24fps source to my 1080i LCD panel (1920x1080 at 30Hz).

Wednesday, March 25, 2009

Cracking Signed ActiveX Controls

Ever come across an ActiveX control you can't afford to buy but wish to use for your own little pet project? Especially those readily available for download, but annoys the hell out of you when you try to use it as it keeps painting "Evaluation Version" all over itself?

Well, from time to time, I develop pet projects to keep myself entertained. Being a perfectionist, I just can't stand to see the "Eval Version" message appearing on my applications. Yes, the sole purpose of these apps are just so I could marvel at myself when I finish them, but how would I be able to do that if I leave the "Eval Version" message lying around? I want that newly polished, super shiny feeling you get when you finish something you can be proud of.

So I set out with a mission - to crack the ActiveX control that is sprinkling all those "Eval Version" on itself.

Surprisingly, cracking the several ActiveX controls I've used isn't all that hard - so long as you know a little x86 ASM and have the right tools (such as the W32Dasm for Windows). Most ActiveX controls are smart enough to prevent simple cracks such as looking up the "Eval Version" message and skipping them via a jmp, but in order to draw the text on the screen, the message would still have to be decrypted somehow and placed in the memory. And, THAT is usually the weakest link. What I usually do is, I'd change the opcodes directly in the memory while I step through the ASM in an IDE (I use CodeGear RAD Studio 2007) so I could see the effects immediately. If things go wrong, I'd simply break out of the debug session and restart.

Once you have cracked it, use a hex editor to change the bytes you've changed in the IDE - you'll have to note down a few instructions before and after the ones you're about to change when you were debugging in the IDE, as there may be more than one occurrence of the bytes you search for. For example, there could be numerous occurrences of "33C9" hex, which translates to "xor ecx,ecx".

For normal exe / dll files, patching the file and then doing a final test would've been the end of it. With a signed ActiveX file, however, you'd find that if you try to use the ActiveX in your IDE, it'll complain that the ActiveX cannot be loaded. That simply means that the hash (usually SHA1) in the ActiveX no longer matches the file - and rightly so! This is easily circumvented though - all you need to do is re-sign the file, and then re-import that into your IDE.

Lucky for us, there's no need to un-sign the ActiveX file before re-signing it with our own cert. Here's a link with step-by-step guide for signing an ActiveX file - http://www.pantaray.com/signcode.html

In the next installment, I'd probably blog about cracking signed .NET assemblies, if responses are good for this one.

Wednesday, March 18, 2009

WinAPI functions and GetLastError / WSAGetLastError

Having been using WinAPI for more than a decade, I was surprised with myself for not being more careful with the return value and GetLastError's error code following a WinAPI call. Granted the bug I was facing was not easy to root cause, but that was no excuse as I should've been more careful when coding. We all make mistakes but the difference between a good and bad programmer is that the former is constantly alert of the pitfalls when coding (read: edging toward paranoia) while the latter simply hacks away hoping things will work out fine.

The thing to keep in mind is WinAPI functions don't set Last Error Code unless the function's return value is FALSE (zero) even if GetLastError sometimes returns ERROR_SUCCESS (e.g. TlsGetValue) - it does NOT mean that WinAPI functions will set Last Error Code to ERROR_SUCCESS regardless. If you've made the assumption that all WinAPI function calls will reset Last Error Code to ERROR_SUCCESS (or NO_ERROR) following a call, then chances are your code will work fine so long as the function has not encountered an error, but will fail as soon as it does, because subsequent calls to the function will appear like an error if you rely on just GetLastError for the result. You should ALWAYS read the documentation of each function as their Return Value varies and remember that there will be one scenario where Last Error Code won't be set.

Sunday, February 22, 2009

Avoid AMD at all costs (and Gigabyte too)

This goes for everything - GPU / graphics cards, CPU, software, and even shares.

I recently got my first AMD graphics card and found it to be extremely bad in quality - both the hardware itself as well as the drivers.

My first card was from MSY (VIC Australia) - it was a Gigabyte 4350 (AMD / ATI card). Plug it in to my old machine which was sidelined recently due to an upgrade, but had been running ECS nVidia 9600, I found that the GDDR2 chips are defective. In fact, booting into Vista caused the graphics card to lock-up entirely. After some investigations, I discovered that there are a few frequencies that the card chooses depending on the state of the card - it boots up with a 200MHz GDDR2 RAM frequency (400MHz effective) and runs 3D (load) with a 500MHz (max default) frequency.

Keep in mind that this is the default frequencies (read: NON-OC'ed) from Gigabyte. Just to get a closure and confirm that it is in fact defective RAM as I had suspected, I flashed the video card BIOS with one that runs the RAM at a lower speed and found that it worked. The maximum speed I could get it to run at was 300MHz - a far cry from the advertised 500MHz (1000MHz effective)! Heck, 300MHz? My OLD machine is running 800MHz DDR2 (1600MHz effective). And to put that into perspective, my nVidia 9600GT works perfectly with an overclocked GDDR2 at 1200MHz (2400MHz effective)! Gigabyte and AMD - shame on you!

I'd also avoid Gigabyte at all costs. So far I've owned 5 Gigabyte motherboards - none of which I could go to the shop, purchase it, and plonk in a CPU and install OS. Gigabyte = troublesome. I'd have to return it and get it exchanged for a new one. It's not the 2nd board that'll work but the 3rd! Most won't even get past POST. Apparently, it's no different with a graphics card.

Back to the graphics card issue - this time the shop ran out of the graphics card - so I got to the 2nd, and that did not work either. Eventually we settled for a refund. I immediately drop by Centrecom and got myself an Asus 4350. Dropping it into my system and it immediately worked - 3DMark06 ran flawlessly (discounting the performance of course).

Then, I decided to watch some blu-ray contents and to my surprise, it stuttered like mad. Why? Because it's using my old CPU to decode in software - no UVD! Keep in mind this is with Media Player Classic - HC, which used to accelerate blu-ray with my nVidia 9600GT (which was running a BETA driver, as opposed to the AMD 4350 which was running the official Catalyst 9.1).

After spending days reinstalling Windows and drivers, I still had no luck. Eventually, I stumbled upon AMD's own forum while looking for solutions and found that people have been complaining about the same thing - Catalyst 9.1 broke all DXVA support in Windows XP! I immediately did a driver feedback via their website and told them the issue.

A month later, Catalyst 9.2 was released. Still broken!

I bought this card for the sole purpose of accelerating HD contents - if the card can't do it, then stop advertising it! At least in Australia, the law protects consumers in this regard - we can return it if we find that it does not do what it's advertised to. I'm sure in US consumers have no rights whatsoever and get lied to with false advertisements.

My advice, stick with Intel and nVidia. Heck, even Intel's G45 integrated gfx would've been a LOT better - yes there're some issues with 24Hz playback (1920x1080p 24Hz that is, and not all TVs support that) but for all other modes, it accelerates HD contents flawlessly, just as advertised.

But, with that said, I'd like people (read fanboys) to continue buying AMD just to keep Intel and nVidia in check (quality, performance and price). :-)

Tuesday, February 17, 2009

Performance Monitor / Counters not working in XP

Strangely enough, the XP machine I use in the office has never had the performance counters working.

If you tried running SysInternal's pslist (I use it mostly so I could do pskill for the issue I blogged about here), you'll get a message saying, "Processor performance object not found on Run Exctrlst from the Windows Resource Kit to repair the performance counters."

Or, if you try running the Performance MMC snap-in (In XP it's under Control Panel --> Administrative Tools --> Performance), you'll get no response for a minute or two, and when the window appears, the red line in the graph will not move (and you won't be able to add any graphs for monitoring either).

Or, if you try to use performance counters in .NET (e.g. for CPU Usage monitoring), you'll get an exception complaining performance counters are not available.


What's the problem? To be honest, I don't know and I don't care enough to find out, but I do care enough to make it work.


Here's how:
  • Install Windows Support Tools which could be found on Microsoft's website (here's the XP SP2 version which will also run in SP3 - http://www.microsoft.com/downloads/details.aspx?FamilyID=49ae8576-9bb9-4126-9761-ba8011fabf38&displaylang=en)
  • Once you've installed it, run exctrlst.exe
  • Make sure that PerfProc and PerfOS have their Performance Counters enabled (select the entry and verify that the "Performance Counters Enabled" option is checked)
  • Once you've done that, close the window and run PsList again to see if it works
  • If not, continue reading. You'll need a copy of Windows installation CD for the following steps

PsList is still not working:

What we'll be doing is manually replace some of the files with the original ones (I'm guessing at some point, Microsoft released a hotfix which broke the files).
  • Go to the I386 folder on your Windows CD
  • Make a backup of C:\Windows\System32\perfc009.dat and C:\Windows\System32\perfh009.dat (we'll be overwriting them)
  • Expand perfc009.da_ to C:\Windows\System32\perfc009.dat (expand perfc009.da_ C:\Windows\System32\perfc009.dat)
  • Expand perfh009.da_ to C:\Windows\System32\perfh009.dat (expand perfh009.da_ C:\Windows\System32\perfh009.dat)

Try running PsList again - it should work now.


If all of the above failed, there's one other resource you could read up - How to manually rebuild Performance Counter Library values.