Over the last few years I’ve worked with a number of engineers that have reported out of memory errors when encoding high definition (HD) video using the Windows Media Format SDK. This issue typically only occurs on 32 bit systems. As we know on...

The Multimedia Timer APIs (MM Timer APIs) get their high accuracy by using the Programmable Interrupt Controller (PIC) built into the hardware on the machine. By default Windows specifies a PIC duration of about 10 – 16 milliseconds. Every time...

Potentially Breaking Change (*IMPORTANT*): Intelligent Connect adds a level of indirection on Win 7 that may have a major impact to DirectShow developers. Starting in Windows 7, DirectShow has a list of preferred filters for certain media subtypes...

The other day we had a major OEM report an issue with the WASAPI. In particular when they found that when they called “IAudioEndpointVolume::QueryHardwareSupport” it would occasionally return unexpected results for USB web cam devices. Most...

We recently had an engineer report a strange exception when displaying .hta files via mshta.exe. If you embed the Windows Media Player OCX control (WMP) in a web page and then start playback of a file, you will get an exception like the following: ...

A colleague of mine in Japan recently found this very interesting issue in Windows Media Player (WMP) on Windows XP. From what he found WMP returns the wrong duration value when playing back MPEG1 files via HTTP. This only appears to occur if the file...

I get this series of questions from different developers from around the world at least once a week. Q. I want to use DirectShow (Windows Media Format SDK, WASAPIs) from my C# (VB.net, managed) code. Why doesn’t Microsoft have a COM interop library...

I have been working with an engineer for weeks trying to figure out why we were not able to push to multiple publishing points on the same server using the Windows Media Format SDK. I know that there was a bug in the Format SDK that prevented multiple...

It looks like the 64 bit version of the Windows Media Format SDK .lib static library files are not where you would expect to find them. If you go to the Windows Media SDK downloads page, there is a happy little link for the Windows Media Format 11 SDK...

There are some rather interesting misunderstandings surrounding Direct Media Objects (DMO). I talked to one engineer the other day that called DMOs inferior to DirectShow filters. While I personally think that DirectShow is one of the most amazing technologies...

I was talking to a DirectShow engineer the other day that was having issues rendering URLs using DirectShow on XP and Vista. He noticed that the behavior was very different between the two operating systems. Luckily I was privy to a very interesting conversation...

When reading a stream from a location such as a media resource object, and then calling “MediaElement.SetSource” may return “AE_INVALID_FORMAT_ERROR”. If you construct a “MemoryStream” using your “Stream”...

When connecting to Windows Server 2008 through remote desktop choosing to leave the audio on the remote machine does not work as expected. Although the option shows up on the remote desktop application, if you select it and then connect, the audio is...

I was in training a few weeks ago (WMS 2008 new features) and found that no matter what I did I was not able to get hotfix KB929182 installed on my Vista lab machine. The hotfix would act as if it installed correctly but the affected DLLs were not updated...

Here is an interesting issue I ran across writing Windows Media Player (WMP) custom DSP plug-ins. When I am prototyping a new filter or plug-in for DirectShow or WMP, I will usually write my transform’s algorithm using a single format / media type...

One of the things that a lot of DRM savvy CDNs are doing is to use WM Encoder to add WM DRM to their content without actually re-encoding. This is basically a copy operation from the input file (WMV) to an output file (WMV). The samples are never decompressed...

I wrote this sample code a while back to show how to validate the latest individualization version when using predelivery. Here are a few tricks that you need to do to make this work. Namely, you need to parse the “ClientInfo” XML fragment...

If you write your own DirectShow based Audio Renderer and want it to work inside WM Player 11 don’t derive it from CBaseRenderer. If you use CBaseRenderer, A/V playback in WM Player may hang. Unfortunately it doesn’t hang all the time. The...

I ran into an issue using the WM Format SDK DRM Stub Library the other day. When we were trying to decode and playback some DRM encrypted files we saw a “NS_E_DRM_LICENSE_NOTACQUIRED” error when using the “Audio Player” sample...

There are a few limitations to the supportability of the Windows Media Encoder 9 series application and SDK. Microsoft has extended support for this product for the next year or so. Hopefully if you are reading this you are aware of the next generation...

I found an interesting problem when dynamically changing the input format of the WM Encoder while encoding. In other words if you are capturing from a single digital capture card and the card can change the input resolution dynamically then WM Encoder...

Q. When playing back a DV encoded AVI file, what does the AVI Splitter do when it detects a zero byte sample (zero byte index) from the Async File Source? A. From what I see in the code the AVI Splitter doesn’t do anything when it detects a zero...

Q. When NTSC (29.97 interlaced) video is being fed to the VMR9 with a custom allocator/presenter, PresentImage is being called 60 times per second. You expect 30 times per second. A. This is by design depending on the type of deinterlacing that you...

UPDATE: The code referenced on this page is written in ASP / VB Script. I recently created a complete ASP.net code sample that does everything this code does and more. I would recommend that you check it out by going here: http://blogs.msdn.com/mediasdkstuff...

I ran into an interesting issue with DirectMusic yesterday. When you use PlaySegmentEx to repeatedly play MIDI content, after about 18 - 20 days of constant playback the API stops playing the content as expected. DirectMusic builds a DirectShow graph...