I'm doing a DVD collection of my daughter with my digital video camera. I noticed that I have one miniDV tape completed with approximately 1 hour of video on it. After editing I have 4 files with 9 minutes and 26 seconds worth of video in each. Each file is 2 Gigs. I'm accustomed to DVD movie editing and I wonder why the files are so much smaller but hold more. _X_X_X_X_X_[small]You are entering a world of pain Smokey.[/small]
To calculate the size in kilobytes (K) of one frame of uncompressed video, use the following formula: Frame size K = ([Pixel Width x Pixel Height x Bit Depth] / 8) / 1024 Where 8 represents an 8-bit byte, and 1024 equals the number of bytes per kilobytes. For example, the size in kilobytes of an uncompressed frame of full-size (640 x 480), 24-bit video is: Frame size K = ([640 x 480 x 24] / 8) / 1024 = 900K To determine the file size of one second of uncompressed video, multiply the image size by the number of frames per second (fps). For example, one second of uncompressed, full-size, full-speed (30 fps), 24-bit video is: 900K x 30 = 27 MB To determine how compression affects file size, divide the file size by the compression ratio. For example, a 10:1 compression ratio will make a 27 MB file 2.7 MB. The following information compares the disk space requirements for NTSC video (640 x 480 and 29.97fps) compressed using various date rates. The data rate information is shown for each of the standard data rate calculation methods: by frames and by seconds: 60 KB/Frame: 1.8 MB/sec 9.25 min/GB 80 KB/Frame: 2.4 MB/sec 6.94 min/GB 100 KB/Frame: 3.0 MB/sec 5.56 min/GB 120 KB/Frame: 3.6 MB/sec 4.63 min/GB 140 KB/Frame: 4.2 MB/sec 3.97 min/GB 160 KB/Frame: 4.8 MB/sec 3.47 min/GB 180 KB/Frame: 5.4 MB/sec 3.08 min/GB 200 KB/Frame: 6.0 MB/sec 2.78 min/GB The DV standard of 720 x 480 video with 5:1 compression requires 3.6 MB/sec and 4.63 min/GB. -courtesy of Adobe Ergo, your 2GB = 4.63min/GB * 2
miksirhc, Excellent work! I'll try different rates of compression vs. quality to find an acceptable medium. Thanks.
As discussed on this and many other forums, the most suitable dimension is somewhere between 640X480 and 320X240. I find that unless I project my final video onto HDTV, any size higher than 640X480 is ineffective. Sony Professional PVM20M2U has 600 lines of resolution which makes my finished work flawless. However, Toshiba 27AF42 even with 3-line digital comb filter makes little if not no difference between 640X480 and 320X240. Perhaps this is due to difference in bit-rate of 3.6Mbits/second verses 5.1Mbits/second, respectively. Choosing which frame ratio, I suppose, is left to each of us to decide whether ‘is my precious memory worth putting in 1 disk or 2 disks’. Many users today try too hard to “cram” too much in one disk, hoping to save a buck or two. --my two cents
I'm not quite that sophisticated. I'm afraid I only have a Sony DCR-TRV17. However the finished product looks excellent on my HDTV. Just as sharp as any DVD.
