Various video tasks and suggested solutions =========================================== This document is released to the public domain by Paul Edwards. It is available from www.kerravon.w3.to. This document was written from a combination of research and first hand experience. Some of the research material can be found at: http://members.xoom.com/ksong1222/start.htm http://www.freenet.de/codecpage http://www.buybuddy.com/guide.buddy/11107 http://www.videoguys.com http://www.tomshardware.com http://home.att.net/~desktopvideo/rvd-faq.htm http://freespeech.org/vcd/faq.htm http://www.iki.fi/znark/video/svcd/overview/ http://www.concentric.net/~Psilon/video.html http://www.btinternet.com/~electric.eyes/2gb_limit.htm http://www.members.home.net/richa 1. take vhs videos and convert to vcd/alt, with minimum loss ------------------------------------------------------------ A. The way to do this with least loss is to capture the raw frames uncompressed at full frame rate (704*576*25 for PAL), and then later run a smart deinterlacer (e.g. virtualdub), then one of the AVI to MPEG1 conversion programs (e.g. bbmpeg). The CPU requirements are minimal for this, say Pentium 200, but the disk requirements are enormous, about 32 meg/sec, and for a 3 hour video, 340 gig. Assuming you do the deinterlacing in chunks, so as to not double again the disk space requirements, and you're up for about US$3000. It is important to run a smart deinterlacer, as failing to be SMART about the deinterlacing can produce a WORSE result than if you had just captured one of the (odd/even) fields. Assuming you are doing all this, then, for complex mathematical reasons, even though the destination is 352*288*25, the 704*576*25 capture will yield a "slightly" better result. B. A better idea is to get a Pentium II 300 Mhz or above, and capture in MJPEG using PICVIDEO etc, and then use the AVI to MPEG1 conversion. Cost in CPU is US$100, cost in hard disk space for 3 hours is approx 29 gig, a cost of about US$240, plus the video capture card such as Lifeview Flyvideo at about US$60, so total US$400. C. There is another alternative, which gives lower quality, and invests money in non-generic hardware, which is to buy a dedicated converter such as Dazzle for US$300, whose CPU and hard disk requirements are minimal, say a 386SX and a 2 gig hard disk, say for a total cost of US$400. This is simpler, real time, and portable. D. You can also reduce the CPU requirements of (B) by getting a hardware MJPEG such as Matrox Marvel G400TV for something like US$300, but it would probably be better to invest in a generic CPU than custom hardware in this instance. Total cost of about US$540, although this includes a video card with TV out capability, worth probably US$140, so say US$400 nett. E. You can also capture the raw video at VCD resolution (352*288*25 for PAL) which would take about 30 gig per hour. You need a drive that can do 8 meg/sec sustained, but that's not difficult to achieve with a modern IDE drive, 5400 rpm is fine. This should give a result that is only slightly worse than (A). The limiting factor this way is disk space, unless you can break your work up into sub 1-hour chunks, which you need to do anyway for VCD, you're up for a lot of extra disk space. This is my recommendation. It is not possible to convert directly to MPEG1 in real time with today's CPUs doing a full job. The full job would take about 16 times the power of a Pentium III 500. However, things like WinVCR can do a half-resolution, "adequate" job on a Pentium II 350. 2. record 2-3 hours of TV onto hard disk and play back, skipping ads -------------------------------------------------------------------- The hard disk requirements are as above. To skip ads you need a player that allows fast-forward. Windows Media Player allows you to drag the slider. WinVCR also allows you to do this. 3. operate TV via remote control -------------------------------- You need a capture card with a remote control. For example Liveview Flyvideo with Remote for US$100. I don't know how good the remote or the bundled software is. It is also possible to attach a remote to your PC via a serial port, e.g. using RedRat. I think this is the only way you will be able to have your remote and TV in one room, with the PC come Digital VCR in the other room. I haven't seen any buyable software that ties all these things together. Software that might, now or later, do so, are WinVCR, PowerVCR, DuckVision, MGI Software's Pure Diva (most likely candidate, least buyable), Intervideo's WinDVR, Ligos. However, for the same functionality you can get with ReplayTV/Tivo, ie pausing live TV at full quality, you may need a board that incorporates DVxcel from C-Cube or SM2210 from Stream Machine. I think this is the forefront of technology, which is not to say that Joe Consumer will ever accept it. The term to describe this is DVR for Digital Video Recorder, or PVR for Personal Video Recorder. The latter is more to do with software that remembers what you watch and automatically records it for you. 4. use external TV instead of monitor ------------------------------------- To do this you need any graphics card with TV-out. These are inexpensive, an 8 meg AGP card with graphics out costs around US$50. 5. possibly store more than 3 hours of video by converting to mpeg1 ----------------------------------------------------------------- To make maximum use of your disk space, ie to use your computer as a VCR, you really need to convert to MPEG1/MPEG2 on the fly. MPEG2 appears to be the preferred format for this. You are looking at a Pentium III 600 to do this sort of work, using the software that comes with your video capture card (e.g. ATI All-in-Wonder), or Winvcr as an add-on to an existing video card. Winvcr only does MPEG1 at half-resolution, however it also only needs a Pentium II 350. Another choice is to capture in MPEG4 format. 6. teletext ----------- Make sure your TV tuner card comes with teletext software. Even the cheap Lifeview FlyVideo card for US$60 (without remote) comes with this. 7. play dvd movies ------------------ To do this you need to be able to decode MPEG2 in real-time. You can either get a hardware solution for this, e.g. the Hollywood card for something like US$100, or you can get a software player, e.g. SoftDVD or WinDVD, which may even come bundled with your video card. The minimum requirements to do this in software is about a Pentium II 350. In summary, if you're going to buy a new computer, and want to do all these things, you need to get: 1. Pentium III 600 (US$300) 2. 27 gig hard disk (US$240) 3. capture card with remote (US$100) 4. graphics card with TV out (US$50) 5. a stack of software that works with both (3) and (4), which allows you to: A. capture MJPEG in real-time. B. capture MPEG1/2 in real-time (not full job though). C. convert from MJPEG to MPEG1 D. burn VCD E. play back MPEG1/2 under control of remote, preferably with ability to set parameters (e.g. 15 mins, 3 mins, 14 mins, 2.5 mins) so that ads can be skipped. You can get 3 & 4 combined, and bundled with software to do MPEG2 in real-time, e.g. ATI All-in-wonder, which makes it a good deal, but then you have no ability to use a remote, and you can't independently change capture card & graphics card then. I bought the following hardware: AMD K7-600 28 gig Seagate 7200 rpm drive 128 meg ram ATA66 on motherboard (motherboard SD II) Diamond Viper II 32 meg Graphics card Lifeview Flyvideo without remote Note that I went overboard with the graphics card for unrelated reasons, and got the 7200 rpm drive because there were no 5400 rpm cheaper alternatives. I also didn't get the remote on the video capture card because I didn't expect a cheap card to actually work, I just wanted to experiment with it before buying the "real" one. I would tentatively recommend the generic hardware: 8 meg AGP video card with TV-out (US$50) AMD K7-600 (US$200) 128 meg RAM (US$100) ATA-66 motherboard (US$120) 28 gig drive (US$200) with a mind to getting an even bigger hard drive. And the following specialised video equipment: Lifeview Flyvideo with Remote, for video capture (US$100) AVI_IO/VirtualDub to capture more than 2 gig files (US$25/free) Picvideo to capture MJPEG real-time (currently free!) virtualdub to deinterlace MJPEG (free) bbmpeg (not vfw version) to convert MJPEG to MPEG1 (free) winvcr to capture MPEG1 real-time at VHS quality (US$50) Nero CD Burner to burn VCD (US$50) Miscellaneous information: If buying a ~30 gig drive for video, 5400 rpm will be fine as almost all can do better than 8 meg/sec, which will allow just 1 hour of video to be stored at half-resolution uncompressed. Unless you have some application that requires just 15 minutes of video, and you want to store it at full resolution uncompressed, then that puts the requirements up to 32 meg/sec, which you can't do on any of the single IDE drives anyway. So just get the cheapest drive, and double-check that it can do 8 meg/sec using e.g. raptest from www.canopuscorp.com. Another thing that should be noted is that there are "digital VCRs" on the market as a stand-alone system, for something like US$500-US$1000 which allow you to do more sophisticated things than today's PC software allows, like pausing live TV, watching one show whilst recording another, and previewing multiple shows on the one screen. I expect it should be possible to do all this on your computer, but it's early days at the moment. TiVo and ReplayTV are two players in the stand-alone market. If you are capturing TV broadcasts, you can get even higher quality by doing doing the following (from Bas Uterwijk): I would tape all the cable broadcasts on DV using a superVHS output of my tuner/TV/VCR connected to a MiniDVcamcorder with DV/in. I would then convert them to Divx video with interleaved high quality mp3 sound. this way you can get 2 or 3 episodes on a cd with a much better quality than VHS. If you don't cram too much footage on it, you hardly will see the difference between your self made cd's and a DVD. Another suggestion was to go from Analogue TV (since cable TV is compressed, and usually subjected to the channel name being superimposed) onto MiniDV tapes, then leaving it there until DVD becomes an affordable option.