Zitat:
Zitat von goldwingfahrer
Das ist eigentlich der erste Schritte wenn ich hier ein neues File zur Begutachtung bekomme.Man kann auch MediaInfo dazu einsetzen,kostenlos und taugt auch was wenn man wissen will was das für eine Streamart ist.
Folgende Frames sind gleich:
12+13
24+25
36+37
mehr hab ich nicht nachgeschaut.
Anomal ist auch der "Sprung" von 32 zu 33.
auch hier hab ich nicht noch mehr gesucht.
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hier ist eine seite die sich speziell mit dieser minicam beschäfigt.
http://www.chucklohr.com/808/
ich habe die cam #3
dort is auch die rede davon dass es "duplicated frames" gibt. auch dass die native auflösung von 640x480 hochskaliert in der avi datei gespeichert wird (720x480).
ein paar genauere daten:
Empirical measurements (research methods to follow ...)
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Lens - 45 mm equivalent. The image AOV (Angle Of View) on the width is 43.36 degrees, which is the 35mm-camera-equivalent of a 45mm lens.
See How to Measure the Focal Length. The camera orientation is horizontal with the buttons up.
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Image Shape Distortion - The camera takes an image at 640x480 (Aspect Ratio AR=1.33) and upscales it to 1280x1024 (AR=1.25) in the JPG file. This results in a slight shape distortion that makes circles look like tall ovals.
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Video Shape Distortion - The camera takes video at 640x480 (AR=1.333) and upscales it to 720x480 (AR=1.5) in the AVI file. If played back with square pixels the video will have a slight shape distortion that makes circles look like wide ovals.
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AVI File Rate - 54 to 82 megabytes per minute. Of the few videos that I have taken the AVI rate is 54E6 to 82E6 bytes per minute (3.24E9 to 4.92E9 bytes per hour). 54E6 = 54000000. The file size is limited to (4GB - 2bytes) because it's a FAT32 file system.
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Audio - The audio quality (in the AVI file) is good, but voice quality at less than 18 inch is sometimes over modulated.
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Frame Rate - 30.856 to 30.999. Based on 7 AVI files, the FPS varies as reported by VirtualDub. In one example file the FPS was 30.955 with about 7.5% duplicate frames. A standard rate is 29.97 or 30.0. In one file, of 200 video frames 15 were duplicates (7.5% duplicates). So the rate of unique frames is closer to 28.6 fps. The duplicates were not exactly periodic. Duplicates seem to happen about every 10 to 15 frames. In the playback duplicates are most noticeable when panning or tilting the camera. The rate of duplicates might be dependent on the frame content. Needs more research. Another note:
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USB Read Rate - 8600000 bytes per second moving an large AVI file from the camera flash to a computer SATA hard disk.
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Largest AVI File - Slightly less than 4GB. The camera will record video until the 4GB FAT32 file limit or the battery dies. I charged the battery and recorded the longest video that I could. The camera stopped recording at 3134 seconds (52 min14 sec) and 4293899576 Bytes (99.98% of 4GB) and it played OK. The recording rate was about 82E6 Bytes per minute. 4GB = 4294967296 Bytes.
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