Posted on December 10th, 2011 by admin
Couple months ago I worked on audio conference project…
On first view everything looks pretty easy (what you need just capture video/audio compress it and send to destination + all encoders/decoders already implemented), but when firs beta was ready we found million underwater stones, even if my connection is fast enough it doesnt mean that connection […]
Filed under: Programming, Uncategorized | No Comments »
Posted on October 8th, 2010 by admin
Not sure about everyone, but lots of programmers from time to time got task that on one of stage require to find maximum from unsorted array/memory/… of data. And the best
i was working on detecting microphone sound level. So i received buffer of 16 bit samples and to detect level i had to find max […]
Filed under: Programming | 2 Comments »
Posted on October 3rd, 2009 by admin
Made some changes in samplegrabber and IGetFrame interface now you can define target position and target type, so new IGetFrame:
[ComVisible(true), ComImport,
Guid("2B21644A-D405-4E27-A51C-A4812bE0CE4C"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IGetFrame
{
[PreserveSig]
int getFrame(IntPtr pBuff);
[PreserveSig]
int getSize([Out] out long size);
[PreserveSig]
int getFrameParams(
[Out] out int width,
[Out] out int height,
[Out] out RawFrameFormat format);
[PreserveSig]
int drawText(
[In] IntPtr ptr,
[In] int height,
[In] int width);
[PreserveSig]
int stopDraw();
[PreserveSig]
int getGrayScale(IntPtr ptr);
[PreserveSig]
int getRgb(IntPtr ptr);
[PreserveSig]
int drawTarget(Rect rect, int type);
[PreserveSig]
int […]
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Posted on September 29th, 2009 by admin
I made some changes in native part of library (Samplegrabber) now we can use up to 3 samplegrabbers in the same time and now you can PIvoke for samplegrabber like in bellow code:
[DllImport("DirectShowNETCF.Native.dll")]
private static extern IntPtr GetBaseFilter(int index);
[DllImport("DirectShowNETCF.Native.dll")]
private static extern void DeleteBaseFilter(int index);
also interface IBaseFrame has been changed:
[ComVisible(true), ComImport,
Guid("2B21644A-D405-4E27-A51C-A4812bE0CE4C"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IGetFrame
{
[PreserveSig]
int getFrame(IntPtr pBuff);
[PreserveSig]
int getSize([Out] out […]
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Posted on June 24th, 2009 by admin
If you ever used DirectShow under windows then you know that if you want draw text on preview you can use VMRRenderer, but windows mobile dont provide any way to draw text on preview
I see there only 1 way to solve it - Draw text directly on stream, so we need SampleGrabber to […]
Filed under: Programming | 11 Comments »
Posted on June 18th, 2009 by admin
What is SampleGrabber? this is filter (as a rule Transform or TransInPlace) that goes after filter which samples we are going to grab.
Why do we need SampleGrabber?
1. In windows mobile this is the fastest way to still images, more than that we still uncompressed images (so we dont loose time for encoding/decoding)
2. We can use […]
Filed under: Programming | 50 Comments »
Posted on June 17th, 2009 by admin
Most of us who was trying to use DirectShowNETCF found that resolution of stilled image smaller that it could be, for example my device (Samsung i710) got default resolution on still pin 320×240, but i know that it supports resolutions up to 2Mpx. So that should be fixed
What do we need to change […]
Filed under: Programming | 13 Comments »
Posted on June 13th, 2009 by admin
Ok, most popular question for last week was: “How to still images from windows mobile camera?”
I finished my project little bit earlier that i was planing, so i have free time again and looking for job too
So what do we need? tons extra com interfaces (Ipin, IEnumPins, IEnumFilters, IFileSinkFilter, IAMVideoControl and so on).
Also […]
Filed under: Programming | 14 Comments »
Posted on June 1st, 2009 by admin
In previous post i explained how to play video or audio on Windows Mobile devices using DirectShow.
I`ve received some emails with request to explain how preview video from device camera.
First of all in Windows Mobile SDK in examples you can find C++ exmaple. I`ve seen examples that suggest to compile example from SDK to dll […]
Filed under: Programming | 47 Comments »
Posted on May 29th, 2009 by admin
“DirectShow is a multimedia framework and API produced by Microsoft for software developers to perform various operations with media files or streams.” (c) Wikipedia
I`m not sure what earliest version of Windows Mobile that supports DirectShow, but i`m totally sure that Windows Mobile 5.0 and higher definitly suppor DirectShow.
So if you developing you application on C++ […]
Filed under: Programming | 23 Comments »