// Oprogramowanie Roman Ryltsov
An updated version of LogProcessExceptions utility is given an additional option to create minidump .DMP files for debugged process on user request. This is in particular useful in conjunction with flag choices (on the previous page of the wizard).
Download links:
Recent IP Video Source class/module is not limited to use via registration as a video input/capture/source device. The filter is also registered as a regular filter and can be used programmatically in a regular way: CoCreateInstance, AddFilter etc.
A C++ code snippet below shows how to import interface definition, create an instance of the filter, set it up and start video from a camera:
#include <dshow.h> #pragma comment(lib, "strmiids.lib") #import "libid:BDCE8B49-8895-4605-8278-E9A1FBC889AC" no_namespace raw_interfaces_only raw_dispinterfaces named_guids // IpVideoSource // [...] inline VOID ATLENSURE_INLINE_SUCCEEDED(HRESULT nResult) { ATLENSURE_SUCCEEDED(nResult); } // [...] CComPtr<IBaseFilter> pBaseFilter; ATLENSURE_INLINE_SUCCEEDED(pBaseFilter.CoCreateInstance(CLSID_JpegVideoSourceFilter)); CComQIPtr<IJpegVideoSourceFilter> pJpegVideoSourceFilter = pBaseFilter; ATLENSURE_THROW(pJpegVideoSourceFilter, E_NOINTERFACE); ATLENSURE_INLINE_SUCCEEDED(pFilterGraph->AddFilter(pBaseFilter, L"Source")); ATLENSURE_INLINE_SUCCEEDED(pJpegVideoSourceFilter->put_Location(CComBSTR(_T("http://p.viewnetcam.com:60001/nphMotionJpeg?Resolution=640x480&Quality=Standard")))); ATLENSURE_INLINE_SUCCEEDED(pJpegVideoSourceFilter->put_Width(640)); ATLENSURE_INLINE_SUCCEEDED(pJpegVideoSourceFilter->put_Height(480)); #pragma region Render Output Pin CComPtr<IEnumPins> pEnumPins; ATLENSURE_INLINE_SUCCEEDED(pBaseFilter->EnumPins(&pEnumPins)); CComPtr<IPin> pPin; ATLENSURE_THROW(pEnumPins->Next(1, &pPin, NULL) == S_OK, E_FAIL); ATLASSERT(pPin); ATLENSURE_INLINE_SUCCEEDED(pFilterGraph->Render(pPin)); #pragma endregion
This starts M-JPEG video from Panasonic BB-HCM381A camera available to public online at http://p.viewnetcam.com:60001/nphMotionJpeg?Resolution=640×480&Quality=Standard
UPDATE: ATLENSURE_SUCCEEDED macro in the snippet replaced with ATLENSURE_INLINE_SUCCEEDED – see additional post on this.
C#.NET code snippet will look like this (using DirectShowLib):
using DirectShowLib; using AlaxInfoIpVideoSource; // [...] FilterGraph filterGraph = new FilterGraph(); IJpegVideoSourceFilter sourceFilter = Activator.CreateInstance(Type.GetTypeFromCLSID(new Guid("{A8DA2ECB-DEF6-414D-8CE2-E651640DBA4F}"))) as IJpegVideoSourceFilter; IBaseFilter sourceBaseFilter = sourceFilter as IBaseFilter; (filterGraph as IFilterGraph2).AddFilter(sourceBaseFilter, "Source"); sourceFilter.Location = @"http://p.viewnetcam.com:60001/nphMotionJpeg?Resolution=640x480&Quality=Standard"; sourceFilter.Width = 640; sourceFilter.Height = 480; IPin pin = DsFindPin.ByDirection(sourceBaseFilter, PinDirection.Output, 0); (filterGraph as IFilterGraph2).Render(pin); (filterGraph as IMediaControl).Run(); EventCode eventCode; (filterGraph as IMediaEvent).WaitForCompletion(-1, out eventCode);
Two widely popular applications, which use DirectShow API appeared to be locked in a combat: Google video chat is installing a plugin which registers artificial video capture sources “Google Camera Adapter 0” and “Google Camera Adapter 1”.
As the application does not announce any integration capabilities and is only using video for internal purposes for in-browser video, the approach with system-wide device registration is, well, questionable.
No need to mention, that devices are not operational: they are giving ERROR_DLL_INIT_FAILED (Error 0x8007045A) as soon as you try to instantiate a filter in a DirectShow video capture enabled application.
In-browser Google Video Chat itself does work and shows video from “real” DirectShow devices, including such artificial as created by IP Video Source tool. Google developers prefer still to take data off the device and as soon as possible leave DirectShow domain, as their graph looks like:
Video Capture Source -> Smart Tee Filter -> Sample Grabber Filter -> Null Renderer Filter
While Google plugin developers might need some interprocess synchronization, as the plugin runs in a child “plugin container” process (plugin-container.exe), introduction of virtual video capture devices is not necessary, but is a plain garbage for the operating system and DirectShow environment.
For some reason, Google developers decided to introduce a special thing: they mirror captured video left-to right when it comes to showing picture capture locally. Well, quite possibly it starts a new era in video conferencing: one will not see a direct copy of video sent remotely, but instead he will be given a mirrored thing.
The curious part is, however, the effect the broken devices introduce to another popular software – Skype.
This does not update the software with new features, but there are a few simple things worth mentioning explicitly.
The first is that virtual DirectShow camera device can be set up with both M-JPEG and JPEG URLs. That is, IP cameras which do not implement M-JPEG, or implement it in a buggy way (there is a *huge* deal of such out there) can still be set up to send video as individual video frames/images as long as they implement JPEG snapshots. This is taking place often at a lower frame rate, but still works.
The driver will automatically detect type of URL (by response from the device) and will choose best access method for the given URL.
Second is that if you are looking for IP Video Source software version, such as to check against available updates, it is here on the UI (right click the caption):
The IP Video Source update provides several improvements to the driver:
Updates in greater detail follow.
The video device management window is providing Copy and Paste buttons, which let user transfer device information, including name and settings, through clipboard for various purposes:
The device data is a text, one line per device, lines in comma-separated values (CSV) format.
This implements a DirectShow driver/wrapper over a HTTP based JPEG/M-JPEG streamed video, widely available with IP cameras. Once installed, it provides a Start Menu shortcut to manage video capture devices, where a user can add/remove devices. The devices are automatically registered with DriectShow and are available to applications.
The compatibility list includes:
LogProcessExceptions utility implements a very basic debugger which attaches (see DebugActiveProcess on MSDN) to a running process and monitors its exceptions. Once exception takes place the utility creates a minidump file for the process (see MiniDumpWriteDump on MSDN) so that exception condition could be investigated off-site using debugger.
If you throw C++ exceptions in your C++ code in exceptional cases which indicate necessity to log the condition and possibly check it later, the utility will get the vital information for the application running at production location in environment without fully featured debugger (note that the utility is a simple download-and-run “wizard” style application, with no installation required), or will simply track the error letting the application continue execution without pretty much of an interruption.
The tool will prompt for debuggee process, and follow with minidump type choices and the debugging operation.
