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dvr-ms header states incorrectly NTSC resolution although its stream i


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Summary: When capturing from TV to dvr-ms-file via Win XP MCE, the header of the dvr-ms file signifies that the stream’s resolution is 720x480, while the real stream resolution is 720x576, MCE configured for PAL country and Hauppauge 150 MCE a PAL version. This can have complications for playback.

For example, when playing back in WMP (directly or through avisynth) with ffdshow as MPEG2 decoder, the lowest part of the picture (I assume some 576-480 = 96 lines) is missing. When I consult the ffdshow info and/or avisynth’s info()-function it says the resolution is 720x480. When I switch back to my old nvidia decoder, the picture is displayed correctly in WMP and in file-preferences the correct 720x576 resolution is displayed. This led me to investigate the real resolution of the stream. After consulting various websites and making sure my Hauppauge MCE150 was configured correctly (i.e. to capture in PAL format), I went on to investigate the file itself. Gspot said it was an asf container, so I downloaded asfviewer (http://www.microsoft.com/windows/windowsmedia/forpros/format/ASFViewer.aspx) and opened the dvr-ms file. Under Header object “Stream Properties” one finds the following data:

Stream Properties Object [1] (297 bytes)

Property Value

File Position 9005 ( 0x232D )

Object ID B7DC0791-A9B7-11CF-8EE6-00C00C205365

Object Size 297 ( 0x129 )

Stream Number 1

Version 1

Offset 0

Encrypted False

Security ID 18873916 ( 0x11FFE3C )

Stream Type Specific

Stream Type Video Media

Window Width 720

Window Height 480

Flags 2

Bitmap Info Header

biSize 208

Width 720

Height 480

Planes 1

Bits 0

Compression TEXT: DVR

0000: 44 56 52 20 DVR

Image Size 0

X Pels / Meter 0

Y Pels / Meter 0

Colors Used 0

Colors Important 0

Extra Data Size 168

Extra Data 0000: 00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00

0010: 00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00

0020: 00 00 00 00 00 00 00 00-63 17 05 00 00 00 00 00 c

0030: 00 00 00 00 00 00 00 00-04 00 00 00 03 00 00 00

0040: 00 00 00 00 00 00 00 00-28 00 00 00 D0 02 00 00 (

0050: E0 01 00 00 01 00 00 00-4D 50 45 47 00 00 00 00 MPEG

0060: 00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00

0070: 00 00 00 00 00 00 00 00-02 00 00 00 02 00 00 00

0080: 00 00 00 00 00 00 00 00-D0 C4 C4 C4 49 00 2B 4E I +N

0090: 98 FB 95 37 F6 CE 51 6D-D1 C4 C4 C4 49 00 2B 4E 7 Qm I +N

00A0: 98 FB 95 37 F6 CE 51 6D 7 Qm

This led me to try to change the headerdata (all instances of 480 to 576) and see whether this is causing the playback problems. After I changed the 3 values (those emphasized), the ffdshow codec stated displaying the dvr-ms file correctly (with lower part of the picture displayed and acknowledging it as a 720x576 stream) Further testing showed that changing only the binary data under “extra data”-property from “E0 01” to “40 02” was enough to make the dvr-ms file play correctly with ffdshow in WMP and MCE.

So, the question is: am I the only one or is everyone having this issue AND IF SO, how can one force MCE to write down the header of dvr-ms-files correctly? Help would be appreciated.

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