Video playback on RISC OSBy Martin Hansen. Published: 30th Aug 2004, 11:49:29 | Permalink | Printable
What we've got, and looking forward toIntrigued with digital video playback on RISC OS, Martin Hansen reports on his recent intrepid investigations. It's a messy job, but someone's got to do it.
My daughter, Fran, became a teenager this week although, as I often tell anyone who will listen, she has been acting like one for at least the last couple of years. This manifests itself in many ways but what prompted this article is her emerging passion for rock music played by unsavoury types. A couple of weeks ago, not contented to simply listen to 'The Rasmus' on CD, she began to excitedly wave their CD single at me: track four on the CD, she had noticed, featured a video of the band performing In The Shadows.
I immediately decided not to tell her that her A6 from Stuart Tyrrell could probably play this under WindowsXP or that a DVD player I'd recently seen in Woolworths for around 40 quid claimed to play VCDs (Video CDs), which, I presumed, was what she enthusiastically held too close to my eye-ball to focus on. I had just the machine, I assured her, that was up to the job.
Into the DVD drive on the Iyonix went the CD and the filer successfully opened the computing component on the CD. As you will see from the screen shot there is quite a lot of clutter but what made me smile was the bright red MPEG icon. I dragged it across to my hard disc, noting that it was almost 50MB of data. These days, 50 'meg' is not a lot and perfectly manageable.
I could remember an announcement in one of the June ANS newsletters that KinoAMP, the MPEG movie player, had been upgraded and so I visited Peter Everett's site to download version 0.32. Similarly minded music video enthusiasts, will also need either AMPlayer or DiskSample as KinoAMP needs one of these to play the sound part of the video track. Do read the installation instructions carefully, as I did, and, hopefully, everything will work right away. I discussed getting AMPlayer working on Iyonix in my recent review on drobe.co.uk of R-Comp's MusicMan, so you may want to re-read that if you have problems.
With the applications software in place, simply double clicking the MPEG icon launches the video. I immediately put The Rasmus on full-screen, much to Fran's delight. The results are excellent and this is the first time that my daughter's rated the Iyonix, "very impressive". MPEGs aspire to display 25 frames per second, but if a system can't cope with that rate, KinoAMP will do the best it can and show, say, 18 of those frames each second. Once the novelty of seeing an MPEG play at all has worn off, dropped frames become, I think, quite noticeable and irritating. The Iyonix didn't drop a single frame.
You can play most music video MPEGs from the CD, or the hard disc, although I later found that, to avoid the occasional "hung machine" problem, from RAM disc is best. I initially discovered this by accident. First, I realised that it is a real faff to have to change CDs all the time, as CD singles typically last under four minutes. Then, having got them on the hard disc, I didn't like to see the drive working as if it were in a Windows machine, constantly pulsed and thrashing. Hence the RAM disc solution. A minor annoyance here is that on the Iyonix this is limited to 131MB, and that's enough room for only two MPEGS at a time. Two RiscPC solutions to the RAM disc limit problem, BigRamDisc and Memphis have not, yet, made the jump to 32bit compatibility.
We still have a lot to discuss regarding the playing of all CD singles with a video track on the Iyonix, mainly because, as I found out over the next few days, 70 percent of singles don't have a straight forward MPEG sitting there, waiting for a RISC OS user to pull it off. First, however, let's take a look at what KinoAMP can do on a StrongARM RiscPC.
When I put one of these enhanced CDs into my Viewfinder fitted Kinetic RiscPC, it froze the machine. I'd known for a while that RISC OS 4 had a problematical CD Filing System but this was the first time I'd been seriously inconvenienced by it, and all the more so when a supposed "bug fix" on the internet didn't work for me. I believe that Warm Silence Software's replacement CDFS will cope, or, alternatively, I could haul the MPEGs in via a network link from Iyonix.
I decided to give RISC OS Ltd a call and order the Adjust 4.39 ROMs, which I'd been meaning to do for quite some time, anyway. These came the next day and resolved the CDFS issue for me although another promptly emerged; AMPlayer could no longer seem to access an essential module, the shared C library, correctly. After trying hard to resolve this issue, I decided to switch to using DigitalCD and DiskSample to play the sound part of the MPEGs. Using the link on Peter Everett's KinoAMP website, I downloaded this. I then noticed that one on the files was a bug-fix for earlier versions of Select running DiscSample on Kinetic. As you've probably guessed, this fixed the problem I was having with AMPlayer under the Adjust ROMs on a Kinetic RiscPC.
StrongARM catches its breath
KinoAMP does work on a StrongARM machine but you need to help it all you can and, even then, it's not perfect: frames are dropped. For full screen viewing (only) I had to disable Viewfinder with the command
*Configure ViewFinderEnable 0, having first hooked up an old AKF60 monitor to the non-Viewfinder video-out. This was just as well, as I then dropped the frequency down to 60Hz which neither my modern CRT or my LCD monitor would have displayed. The MPEG was placed on RAM disc and an acceptable result achieved - one that I would not be embarrassed to show to non-RISC OS users.
I've achieved similar results on other StrongARMs; a 233MHz machine with RISC OS 4 and Select 3i3, and another with RISC OS 3.7. Prior to RISC OS 4, you'll need the BigRamDisc utility rather than Memphis, which is too slow, to create the necessary RAM disc. Incidentally, if you need more RAM for your machine, give APDL a call. I bought an extra 64MB for 22UKP including posting and packaging, which, with a 32MB card already in place, plus 2MB VRAM, has given a friend's machine a cheap boost into the video age.
Some readers may be thinking that this is pouring money into a system that simply can't quite cope. However, the truth of the matter is that KinoAMP, whilst being a substantial step forward for RISC OS, is still not optimised to make the most of the RiscPC's hardware. Other software developments are hovering tantalisingly on the horizon, of which more shortly, and KinoAMP 0.32 is where we have got to at the moment rather than, necessarily, being the final word.
Inspired by the initial successes on both Iyonix and the StrongARMs, I decided to aquire as many CD music videos as I could, and as cheaply as possible. An eBay search using "CD single video" is very effective and a day passed writing out cheques for tiny amounts of money. A local second hand CD shop sold me around forty discs at less than one pound each, and I toured the bargain bins at Woolworths, Virgin and HMV both locally and, as the opportunity arose, further afield. A CD fair in Birmingham was disappointing, unless one was willing to spend at least a fiver a time, and often a lot more, which I was not. I've now got 89 of these discs [89? Give that man a medal - Ed] but, as they came flooding in, I quickly realised that, for RISC OS, there is a problem: only 24 of these had an MPEG on them and, of the other 65, 63 feature something called an AVI file and two remain classified as "seriously weird: investigate later".
KinoAMP can only play MPEGs. As I began to ask around I realised that the world of AVIs is not straight forward, and it took me a while, and with some extraordinarily generous help from some busy programmers, before I felt I was starting to understand what an AVI was, never mind about whether RISC OS could, or was ever likely to, be able to play them. In particular, I had some very profitable email exchanges with Adrian Lees and David McEwan. Adrian is pushing along the CinoDVD project which will make DVDs play on an Iyonix, and maybe, depending on how things pan out, on RiscPCs. David has developed a major application in his spare time called Cineroma. Famously, this is being perfected before being released, in spite of wild enthusiasm about how good it already is from beta testers. It is rumoured to play just about any movie format you care to mention. Release dates for both projects have yet to be announced. Personally, my fingers are crossed for Wakefield 2005, but they are difficult endeavours, and much remains to be done with both of them.
I've enthused about Iyonix-Support in the past and in that forum a useful early posting informed me that an AVI was not a single filetype, in the sense that an MPEG is. Rather it was a Microsoft designed wrapper for packaging all sorts of file-types, primarily intended for unpacking via Microsoft's media player. Armed with this knowledge I was able to ask Adrian and David some slightly more probing questions about what an AVI really was.
Adrian Lees was very specific, "AVI is just a way to interleave a number of audio and visual streams. Just imagine that you have 'n' audio streams and 'm' video streams, and you grab a bit of this audio, then a bit of that video, another bit of this audio, and so on. It's a way to combine multiple streams in a single file."
David McEwen was careful to point out that the AVI wasn't just a wrapper to get off and throw away, "The actual container [the AVI wrapper] of a movie file is very important as it contains pertinent information about how to play the movie, tell you the codecs used [of which MPEG is but one] and, for example, the timings for each frame.
I was intrigued by all of this; inside some of these AVI files could simply be an MPEG, but I couldn't manually just remove the wrapper by hand, as I had, perhaps naively, initially hoped.
Adrian again: "Normally, an AVI is used to wrap a single audio stream and a single video stream. In the case of an MPEG, it wraps a single MPEG stream, which is already audio and video into a single AVI stream."
So, where does this leave RISC OS in the mighty quest I'd given it, namely, to play CD pop-music singles with video ? Both Adrian Lees and David McEwen, were up-beat about the future. Soon, you will not have to abandon RISC OS in order to play an AVI.
Adrian Lees thought that Cino should play some AVIs and do so well. He commented, "The fact is that whilst the Iyonix's hardware is not equal in performance to the PCs built in the last three years, our software is greatly under-using what we do have as, indeed, WindowsXP does with what is available to it. Decoding and rendering under RISC OS could be many times faster."
And David had this to add, "Cineroma will not need anything done to the majority of AVI files you are looking at to be able to play them. Like with an MPEG in KinoAMP or a Replay file, you just double click on a file and it will play."
In the meantime, we do, thank's to Peter Everett's efforts, have the new version of KinoAMP; and it's free. If you've got some enhanced CD singles in your collection, do try them out. RISC OS is not fully modern multimedia compliant yet, but further progress seems to be on the way.
KinoAmp VCD compatibility list
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