I am experiencing problems with phonon direct show backend on WinXP. Basically it doesn't work at all for me I've tried it with both 4.7.0 SDK and with version built from sources. In both cases phonon_ds94.dll is located in plugins/phonon_backend/ dir.

Here how I create video player:
Qt Code: 
  1. vp = new Phonon::VideoPlayer(this);
  2. ...
  3. vp->play(QUrl("..."));
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And this is what I've got as output during debug run qt-creator:
Qt Code: 
  1. Exception at 0x7c812afb, code: 0x406d1388: Startup complete, flags=0x0
  2.  
  3.  
  4. Exception at 0x7c812afb, code: 0xe06d7363: C++ exception, flags=0x1 (execution cannot be continued)
  5.  
  6. at:
  7. 0     kernel32!RaiseException 0x7c812afb
  8. 1     VSFilter!DllGetClassObject 0x24f8a76
  9. 2     VSFilter!DllGetClassObject 0x24a77f4
  10. 3     VSFilter 0x248459e
  11. 4     VSFilter!DllGetClassObject 0x251ac7c
  12. 5     VSFilter 0x248a53e
  13. 6     ole32!CoCreateInstance 0x775007b6
  14.  
  15.  
  16. Exception at 0x7c812afb, code: 0xe06d7363: C++ exception, flags=0x1 (execution cannot be continued)
  17.  
  18. at:
  19. 0     kernel32!RaiseException 0x7c812afb
  20. 1     VSFilter!DllGetClassObject 0x24f8a76
  21. 2     VSFilter!DllGetClassObject 0x24a77f4
  22. 3     VSFilter 0x248459e
  23. 4     VSFilter!DllGetClassObject 0x251ac7c
  24. 5     VSFilter 0x248a53e
  25. 6     ole32!CoCreateInstance 0x77501ee6
  26. 7     ntdll!RtlAllocateHeap 0x7c9101db
  27. 8     VSFilter!DllGetClassObject 0x24f8b43
  28. 9     ntdll!RtlAllocateHeap 0x7c9101db
  29. 10    VSFilter!DllGetClassObject 0x24f8b43
  30. 11    VSFilter!DllGetClassObject 0x2516646
  31. 12    VSFilter!DllGetClassObject 0x2517c6b
  32. 13    USER32!GetWindowLongW 0x7e4189cd
  33. 14    USER32!DispatchMessageW 0x7e418a10
  34. 15    kernel32!ValidateLocale 0x7c839ad8
  35. 16    kernel32!GetModuleFileNameA 0x7c80b730
  36.  
  37.  
  38. Exception at 0x7c812afb, code: 0xe06d7363: C++ exception, flags=0x1 (execution cannot be continued)
  39.  
  40. at:
  41. 0     kernel32!RaiseException 0x7c812afb
  42. 1     VSFilter!DllGetClassObject 0x24f8a76
  43. 2     VSFilter!DllGetClassObject 0x24a77f4
  44. 3     VSFilter 0x248459e
  45. 4     VSFilter!DllGetClassObject 0x251ac7c
  46. 5     VSFilter 0x248a53e
  47. 6     ole32!CoCreateInstance 0x77501ee6
  48. 7     ntdll!RtlAllocateHeap 0x7c9101db
  49. 8     VSFilter!DllGetClassObject 0x24f8b43
  50. 9     ntdll!RtlAllocateHeap 0x7c9101db
  51. 10    VSFilter!DllGetClassObject 0x24f8b43
  52. 11    VSFilter!DllGetClassObject 0x2516646
  53. 12    VSFilter!DllGetClassObject 0x2517c6b
  54. 13    USER32!GetWindowLongW 0x7e4189cd
  55. 14    USER32!DispatchMessageW 0x7e418a10
  56. 15    kernel32!ValidateLocale 0x7c839ad8
  57. 16    kernel32!GetModuleFileNameA 0x7c80b730
  58.  
  59.  
  60. Exception at 0x7c812afb, code: 0xe06d7363: C++ exception, flags=0x1 (execution cannot be continued)
  61.  
  62. at:
  63. 0     kernel32!RaiseException 0x7c812afb
  64. 1     VSFilter!DllGetClassObject 0x24f8a76
  65. 2     VSFilter!DllGetClassObject 0x24a77f4
  66. 3     VSFilter 0x248459e
  67. 4     VSFilter!DllGetClassObject 0x251ac7c
  68. 5     VSFilter 0x248a53e
  69. 6     ole32!CoCreateInstance 0x77501ee6
  70. 7     ntdll!RtlAllocateHeap 0x7c9101db
  71. 8     VSFilter!DllGetClassObject 0x24f8b43
  72. 9     ntdll!RtlAllocateHeap 0x7c9101db
  73. 10    VSFilter!DllGetClassObject 0x24f8b43
  74. 11    VSFilter!DllGetClassObject 0x2516646
  75. 12    VSFilter!DllGetClassObject 0x2517c6b
  76. 13    USER32!GetWindowLongW 0x7e4189cd
  77. 14    USER32!DispatchMessageW 0x7e418a10
  78. 15    kernel32!ValidateLocale 0x7c839ad8
  79. 16    kernel32!GetModuleFileNameA 0x7c80b730
  80.  
  81.  
  82. Exception at 0x7c812afb, code: 0xe06d7363: C++ exception, flags=0x1 (execution cannot be continued)
  83.  
  84. at:
  85. 0     kernel32!RaiseException 0x7c812afb
  86. 1     VSFilter!DllGetClassObject 0x24f8a76
  87. 2     VSFilter!DllGetClassObject 0x24a77f4
  88. 3     VSFilter 0x248459e
  89. 4     VSFilter!DllGetClassObject 0x251ac7c
  90. 5     VSFilter 0x248a53e
  91. 6     ole32!CoCreateInstance 0x77501ee6
  92. 7     ntdll!RtlAllocateHeap 0x7c9101db
  93. 8     VSFilter!DllGetClassObject 0x24f8b43
  94. 9     ntdll!RtlAllocateHeap 0x7c9101db
  95. 10    VSFilter!DllGetClassObject 0x24f8b43
  96. 11    VSFilter!DllGetClassObject 0x2516646
  97. 12    VSFilter!DllGetClassObject 0x2517c6b
  98. 13    USER32!GetWindowLongW 0x7e4189cd
  99. 14    USER32!DispatchMessageW 0x7e418a10
  100. 15    kernel32!ValidateLocale 0x7c839ad8
  101. 16    kernel32!GetModuleFileNameA 0x7c80b730
  102.  
  103.  
  104. Exception at 0x7c812afb, code: 0xe06d7363: C++ exception, flags=0x1 (execution cannot be continued)
  105.  
  106. at:
  107. 0     kernel32!RaiseException 0x7c812afb
  108. 1     VSFilter!DllGetClassObject 0x24f8a76
  109. 2     VSFilter!DllGetClassObject 0x24a77f4
  110. 3     VSFilter 0x248459e
  111. 4     VSFilter!DllGetClassObject 0x251ac7c
  112. 5     VSFilter 0x248a53e
  113. 6     ole32!CoCreateInstance 0x77501ee6
  114. 7     ntdll!RtlAllocateHeap 0x7c9101db
  115. 8     VSFilter!DllGetClassObject 0x24f8b43
  116. 9     ntdll!RtlAllocateHeap 0x7c9101db
  117. 10    VSFilter!DllGetClassObject 0x24f8b43
  118. 11    VSFilter!DllGetClassObject 0x2516646
  119. 12    VSFilter!DllGetClassObject 0x2517c6b
  120. 13    USER32!GetWindowLongW 0x7e4189cd
  121. 14    USER32!DispatchMessageW 0x7e418a10
  122. 15    kernel32!ValidateLocale 0x7c839ad8
  123. 16    kernel32!GetModuleFileNameA 0x7c80b730
  124.  
  125.  
  126. Exception at 0x7c812afb, code: 0xe06d7363: C++ exception, flags=0x1 (execution cannot be continued)
  127.  
  128. at:
  129. 0     kernel32!RaiseException 0x7c812afb
  130. 1     VSFilter!DllGetClassObject 0x24f8a76
  131. 2     VSFilter!DllGetClassObject 0x24a77f4
  132. 3     VSFilter 0x248459e
  133. 4     VSFilter!DllGetClassObject 0x251ac7c
  134. 5     VSFilter 0x248a53e
  135. 6     ole32!CoCreateInstance 0x77501ee6
  136. 7     ntdll!RtlAllocateHeap 0x7c9101db
  137. 8     VSFilter!DllGetClassObject 0x24f8b43
  138. 9     ntdll!RtlAllocateHeap 0x7c9101db
  139. 10    VSFilter!DllGetClassObject 0x24f8b43
  140. 11    VSFilter!DllGetClassObject 0x2516646
  141. 12    VSFilter!DllGetClassObject 0x2517c6b
  142. 13    USER32!GetWindowLongW 0x7e4189cd
  143. 14    USER32!DispatchMessageW 0x7e418a10
  144. 15    kernel32!ValidateLocale 0x7c839ad8
  145. 16    kernel32!GetModuleFileNameA 0x7c80b730
  146.  
  147.  
  148. Exception at 0x7c812afb, code: 0xe06d7363: C++ exception, flags=0x1 (execution cannot be continued)
  149.  
  150. at:
  151. 0     kernel32!RaiseException 0x7c812afb
  152. 1     VSFilter!DllGetClassObject 0x24f8a76
  153. 2     VSFilter!DllGetClassObject 0x24a77f4
  154. 3     VSFilter 0x248459e
  155. 4     VSFilter!DllGetClassObject 0x251ac7c
  156. 5     VSFilter 0x248a53e
  157. 6     ole32!CoCreateInstance 0x77501ee6
  158. 7     ntdll!RtlAllocateHeap 0x7c9101db
  159. 8     VSFilter!DllGetClassObject 0x24f8b43
  160. 9     ntdll!RtlAllocateHeap 0x7c9101db
  161. 10    VSFilter!DllGetClassObject 0x24f8b43
  162. 11    VSFilter!DllGetClassObject 0x2516646
  163. 12    VSFilter!DllGetClassObject 0x2517c6b
  164. 13    USER32!GetWindowLongW 0x7e4189cd
  165. 14    USER32!DispatchMessageW 0x7e418a10
  166. 15    kernel32!ValidateLocale 0x7c839ad8
  167. 16    kernel32!GetModuleFileNameA 0x7c80b730
  168.  
  169. WARNING: Phonon::createPath: Cannot connect  Phonon::MediaObject ( no objectName ) to  Phonon::VideoWidget ( no objectName ).
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Does anyone has any ideas?