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Old 20th February 2021, 23:55   #1  |  Link
thghgv
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Join Date: Feb 2011
Posts: 29
CCdata gradually corrupted in graphedit

Hello all

I am attempting to do captures of vbi CCdata with a hauppauge HVR-1950 capture device from a composite video stream of dishPVR recorded material from a dishnet sat receiver. I have succeeded in this task a few times but it seems that over the course of a couple of days using the same graph the ccdata becomes corrupted - as in misspelled words, dropped letters, whole pieces of dialog sometimes just gone etc... I built the graph with a active-movie check monitor to display the video stream and captions in order to be able to make certain the captions are intact. With this graph the captions being captured to the binary file are pretty much WYSIWYG. So when I see garbaged up captions I am recording garbage up captions to file. I using the attached graph. Pretty simple CCdata display onscreen that record the captions to a file via a dump.filter connected to a spare "cc" pin on the CC decoder filter.

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I went so far as to build a host machine with WINXP-Pro 32b and simply installed the needed softwares to do cc captures - WinTV 6, the HVR-1950 drivers, Graphstudio. Mainly what has worked for me is to dump the raw CCdata to a file and then decode that .BIN file to a .SRT subtitle file via CCextractor.

This all works great except when I start seeing closed caption corruption showing up on the video check display in graphedit. On this last WinXP build every thing was running along fine for a couple of days and then today I started getting corrupt captions again. I can turn on the DishSat receiver's CC display as a check and looking at the captures being decoded by that device I see NO corruption. This issue is of the DShow filtering, graphedit itself or something else I cannot put my finger on. I have swapped cables and devices etc, and verified this is NOT hardware related. The host machine is not on the internet and the OS install is fresh.

Has anyone ever experienced this gradual corruption of captions using graphedit before?

Last edited by thghgv; 21st February 2021 at 00:05.
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