VCR Syncronization

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When capturing a certain time sequence within a video it is difficult to use the pause button and the PC keyboard to synchronize the capturing process. Further it is important to ensure that most of the sequence of interest is part of the captured sequence. Therefor a lager amount of video data has to be captured even though practice can compensate for this approach.
Current VCR equipment using PC remote control is at the moment quite expensive and the software provided with the equipment is also very bad.
At the moment the RealCap module supports the synchronization of the capturing process using Panasonic VCR models AG-7350 and AG-5700.

New: The RealCap has just been changed to be compatible with a modified Panasonic AG-2550C with a special BCD-control interface. Support for other models are under development. In the future it will be possible to   syncronization the capturing using the playback facilities of normal camcorder. This version of the RealCap is sceduled to be delivered in late 98.

The basic idea with the VCR synchronization is to automatically start the VCR before the capturing process from the computer is initiated. To make this possible it is necessary to ensure that the VCR is in proper speed before the images is put to disk. If the speed of the video tape is not correct the first images will be incorrect/jittered. The time for the VCR to be in proper speed is very individual. If fx. the VCR has been extensively used the friction in the mechanical parts will be different from a brand new and the time for attain the proper speed different.

To compensate for this time slack of speed development it is possible to setup a delay from VCR play to capturing process start. Refer to the Capturing preferences for further details on how to setup the Delay option.

Improve time for build up video tape speed: When searching for the video sequence on the video that needs to be captured it is wise to position the VCR in pause mode instead of stop mode. The time for the VCR to build up the proper speed is much longer in stop mode than in pause mode. This is due to the fact that the video tape is released from the video head in the stop mode. The time for the VCR to grasp the video tape unto the VCR head is in many cases more than 1 sec.

There is no way to check the time it will take before the VCR has build up a proper speed where the images are OK. Try play with the delay time and minimize it to about 500ms. This time is properly to small for the VCR to build up the speed. Capture a sequence and use the trimming dialog to verify the image quality.

After the Capturing process has been configured with Auto start and the proper delay the capturing process is started in exactly the same way as normal capturing process.

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