View Full Version : AC3 dshow failure

15th July 2004, 20:37

I have an .AC3 file which causes strange behavior of DirectShow based players. It needs ca. 5 minutes to load the file before playback. The file is 350 mb large and source is a DVD. It was demultiplexed with newest DGIndex.

Decoding with Azid 1.9 shows no errors in bitstream and content.

I testet with GraphEdit, WinMP 6.4 and MPC. GraphEdit displays the graph after the unusual "loading" time. Playback and seeking works fine then. I switched the AC3 decoder filter without success, so I assume the AC3 parser filter requests to read the whole file before playback. But it takes much less time to copy the file. CPU-load was at 10% during the process, so I think the content was not decoded.
MPC's internal AC3/DTS parser shows the same issue as the Windows AC3 Parser (Win2k+SP4+DX9).

Does anyone know about this issue and how to get rid of this?


from AZID's output:

[00:00:00.000] +------ BSI -----
[00:00:00.000] | Bitrate: 384 kbit (48 kHz)
[00:00:00.000] | Mode: Complete Main (CM)
[00:00:00.000] | Audio mode: 3/2 L,C,R,SL,SR+LFE
[00:00:00.000] | Center mix level: -3.0dB
[00:00:00.000] | Surround mix level: -3.0dB
[00:00:00.000] | Dialogue level: -27dB
[00:00:00.000] | Mixlevel: 105dB SPL
[00:00:00.000] | Roomtype: Large room, X curve monitor
[00:00:00.000] | Stream: Copyright protected, Original stream
[00:00:00.000] +----------------
[02:18:02.688] +------ STATS -----
[02:18:02.688] | Decoded frames: 258834
[02:18:02.688] | Peak signal level: -6.7dB
[02:18:02.688] | Ch0: -8.4dB
[02:18:02.688] | Ch1: -6.7dB
[02:18:02.688] +------------------