Process mute Technology in Delphi-XP

Many browsers have this function, and the implementation principle is the same. The voice source is based on flash, such as Flash games and video players.

Flash voice is implemented through the winmm. dll: waveoutwrite function. Therefore, we only need to "take over" this function.

The following code is a previously written module. For the mute of flash, the code is rough. ^_^

 

Note: The following code only applies IAT hook to the Flash module.

XP passed the test

Unit flashmute; interfaceuses windows, sysutils, classes, strutils, tlhelp32, mmsystem; Type tflashmute = class private class var flag: Boolean; public class function modify_waveoutwrite: Boolean; Class procedure enable; class procedure disable; end; implementationfunction mywaveoutwrite (hwaveout: hwaveout; lpwaveouthdr: pwavehdr; usize: uint): mmresult; stdcall; begin if tflashmute. flag then zeromemor Y (lpwaveouthdr. lpdata, lpwaveouthdr. dwbufferlength); Result: = waveoutwrite (hwaveout, lpwaveouthdr, usize); end; {tflashmute} class procedure tflashmute. disable; begin tflashmute. flag: = true; end; Class procedure tflashmute. enable; begin tflashmute. flag: = false; end; Class function tflashmute. modify_waveoutwrite: Boolean; var hsnapshot: thandle; me32: tmoduleentry32; found: Boolean; baseaddr: DWORD; DoS Header: pimagedosheader; ntheader: pimagentheaders; importdesc: required; ITD, itd2: pimagethunkdata; iibn: required; MBI: tmemorybasicinformation; begin result: = false; // list the current process module, find flash ?. OCX hsnapshot: = callback (th32cs_snapmodule, getcurrentprocessid); If hsnapshot <> export then begin me32.dwsize: = sizeof (tmoduleentry32); found: = module32first (hsnapshot, me32 ); while found do begin if containstext (me32.szmodule, 'flash') then begin if sametext (extractfileext (me32.szmodule ),'. OCX ') then begin baseaddr: = DWORD (@ me32.modbaseaddr ^); dosheader: = @ me32.modbaseaddr ^; ntheader: = PTR (baseaddr + dosheader ^. _ lfanew); // traverses the input module importdesc: = PTR (baseaddr + ntheader. optionalheader. datadirectory [1]. virtualaddress); While importdesc ^. name <> 0 do begin ITD: = pimagethunkdata (baseaddr + importdesc ^. originalfirstthunk); // point to the function name RVA or function number itd2: = pimagethunkdata (baseaddr + importdesc ^. firstthunk); // point to the function address // traverse the input function while ITD ^. addressofdata <> 0 do begin // function imported by function name if itd ^. addressofdata and image_ordinal_flag <> image_ordinal_flag then begin iibn: = pimageimportbyname (baseaddr + ITD ^. addressofdata); // find winmm. DLL: waveoutwrite if sametext (string (pansichar (@ iibn ^. name [0]), 'waveoutwrite') then begin if virtualprotect (@ itd2 ^. _ function, sizeof (DWORD), page_execute_readwrite, @ MBI. protect) then begin itd2 ^. _ function: = DWORD (@ mywaveoutwrite); Result: = true; end; break; end; Inc (ITD); Inc (itd2); end; If result then break; INC (importdesc); end; If result then break; found: = module32next (hsnapshot, me32); end; closehandle (hsnapshot); end;