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Post by silverdragon on Oct 6, 2015 5:24:22 GMT
Ahhhh... erm, not quite. The file may be called an "Image", but its still "Burned on via laser". it has the file type .iso... Form File type ISO 9660 which is a file "type", such as FAT-32 or NTFS are also file "Types" The image file is a complete file including directory and finalising that is put on all in one go, without having to bother the processing of the computer or equipment to create a directory, which in burning a normal list of tracks to put on, has to be done by the burning process. More or less, its seen as a "Single track" from start to finish. This takes less space, as the computer doesnt have to create a directory tree to hold that information, and doesnt have to create the directory, nor the finalising file. Its a form of "Zip file". It takes less handling in transfer. Conventional creation of a CD required that the computer creates a "Temp file" of all the information you wish to burn to the disk, then verifies that it will fit, so all the information first has to be transferred to that part of the Hard drive, and then that whole file is transferred "in one" from that temp file to the new CD/DVD. The .iso is the short cut that negates that transfer to temp file, as the image has already been created. The way that is done is that a "image" of the original temp file is taken, and used, and stored, to save time. Its also haw backups (compressed) are made, creating an "Image" file saves directory space and hard-drive space, as no spaces are left on the HD for file changes. As the files themselves can contain boot sectors and all that type of information, they are often used to create bootable disks, such as "Live" cd's for Linux. Some more info... From Wiki, which I refer to as its a lot easier to c&p that write all that down, and its accurate "Enough"?... en.wikipedia.org/wiki/ISO_imagealso this may be of use. en.wikipedia.org/wiki/Disk_image |
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Post by silverdragon on Oct 6, 2015 5:36:42 GMT
If you are going to the commercial "Vast runs" of BIG label (warner brothers Virgin and such labels) of factory produced records, yes.
Smaller recording studio's use the burn method.
I can see where the confusion lies in this, I thought we were talking abut smaller studio's as we started with home stereo, I hadnt realised we had jumped into the Million Quid range of price?...
I have questioned the rarity of the double-side disks, especially in games consuls, and it all hinges on "Confusion".
To start with, the extra cost to "Flip the disk" to write the other side was put into question.
Fist it has to be ejected spun and cooled if its a burn process.
If its a pressing process, the disk has to be made thicker.
The number of failed pressings and failed burnings doubles, then quadruples, as perfectly good side A's get ruined by "coaster" side B's, and vice versa, and then the verifying process done after the two sides have finalised, picks up one or the other?...
Cost wise, its easier and cheaper to produce double-disks with disk 1 and disk 2 written on the label.
Also end users complained about not being able to read the label and putting the disk in upside down by mistake.
End user prefers a double disk to a single double sided disk.,...
Also some machines refused to take the extra thick disks.
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Post by c64 on Oct 6, 2015 10:21:25 GMT
actually, DVDs are made in both single and double sided varieties. you can tell the difference because the single sided ones have a label painted on the other side. here, on DVD-R discs there was also a grand idea by one manufacturer called "lightscribe" they made their discs and drive mechanism so you could insert the disc upside down in the tray and it would use the record laser to "burn" whatever labeling you wanted to on the top surface of the disc. (however it was prepared to accept that, I never actually did it, but Mrs TLW's old laptop has a lightscribe drive in it.) Yes, there are many different systems how to label a disc. It doesn't matter if CD, DVD or Bluray, its just the label side which has nothing to do with the data layers. There are discs with a paper-like surface you can print on with inkjet printers. Then there is Lightscribe which had simply vanished in 2006 (when the website just vanished). Lightscribe Discs have a photosensitive label and some kind of barcode as an inner ring in the label. Originally there were two additional lasers installed in the top of the drive. One weak one to keep track of the "barcode" and an extra strong laser to blacken the photosensitive label layer. Later drives had the "barcode" laser installed in the bottom and the R/W drive laser was beefed up to do everything else. The barcode makes sure each ring of label writing starts at the same disc angle. The problem with this system is that the label is only black/white with low contrast and it degrades when left in the open. In direct sunlight, the label will fade within a week, in an office environment it fades in a year or two. One of the drive manufacturers came up with a software hack which burns the label over and over to increase the contrast but this makes the label writing a lot slower (over 20 minutes) and since the process isn't that precise, the image can become more blurry. The resolution isn't that good anyway and you can often see the spiral in which the image was burned. At the same time, a different system was available, the "Labelflash". When you burn a CD/DVD, the part which was written changes colour slightly. Labelflash can burn a bitmap image onto the unused surface and by burning more intense, you get a holographic looking picture on the data layer of a disc. If you use a double sided DVD-R, you can burn a full sized label onto one side and the data to the other side. There also were "Labelflash" discs available which offered a much more sensitive layer on the backside (the label side) which gives you more contrast and/or different colours. Those special Labelflash discs are hard to obtain nowadays since the system is also "dead" since like lightscribe, it won't give you results that are good enough. But with a Labelflash writer, you can still put your logo onto the data side of any CD and DVD. |
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Post by c64 on Oct 6, 2015 10:37:28 GMT
Mrs TLW's project of the day: take out the Harman Kardon audio system that we haven't been using because I needed to get behind the cabinet and figure out where something came loose, and left the left channel dead, and get rid of it in favor of a new all-in-one set that will have surround sound from the movies, but doesn't have a radio reciever, and won't talk to the CD changer, cassette deck, or playstation. which is okay, because it looks like she plans to get rid of all of them, too. I guess I can add a stereo to the list of things I used to own. (edit: and I also found out that the thing might have come loose because of her habit of poking around behind the cabinet with the vacuum.) What's to talk to a CD changer of cassette deck? Those just have RCA analog connections. True, most A/V receivers use the HDMI connection for the audio, but they all still have RCA analog inputs for older equipment. Not any more! But you can buy converters for less than $10. My dad now has much more video and network equipment than I do. It all had started with a satellite system I gave him years ago for his birthday. One that even works perfectly during a thunderstorm or blizzard. Then I gave him a 5.1 sound system and later receivers with recording capability. Then his provider announced to stop land line telephone service in 2016 and a good offer for IP telephone and the TV entertainment package for almost free. While I can record one sdTV and one SD/HD channel and play back 4 streams from anywhere at the same time, my dad can record 8 SD/HD channels at the same time. Last time I had visited him, I fixed a problem he had. His living room TV has a long delay. It buffers a second or two of stream, analyses it and converts the data to perfectly match the screen with best quality. With the 5.1 system fed by the receivers, the sound isn't delayed so first you hear the voices and then you see the actors speak. The solution was a €3 optical audio to RCA converter box I had ordered in China. Now the TV can feed the delayed audio back to the 5.1 system and he still can switch to any receiver to listen to a radio station without turning on he TV. I think I give him an IP radio for Christmas and a 16-port network switch for his living room for his birthday in spring. |
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Post by c64 on Oct 6, 2015 10:41:43 GMT
What's to talk to a CD changer of cassette deck? Those just have RCA analog connections. True, most A/V receivers use the HDMI connection for the audio, but they all still have RCA analog inputs for older equipment. you haven't seen an all-in-one box set system, have you? Yes, this box is called Smartphone or media server playing to any TV and amp in your network by the DLNA or UPnP standard. |
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Post by c64 on Oct 6, 2015 10:53:51 GMT
actually, DVDs are made in both single and double sided varieties. you can tell the difference because the single sided ones have a label painted on the other side. here, on DVD-R discs there was also a grand idea by one manufacturer called "lightscribe" they made their discs and drive mechanism so you could insert the disc upside down in the tray and it would use the record laser to "burn" whatever labeling you wanted to on the top surface of the disc. (however it was prepared to accept that, I never actually did it, but Mrs TLW's old laptop has a lightscribe drive in it.) There are dual layer recordable DVDs (DVD-R-DL)that have been available for over 10 years now. They hold 8.5G of data and both layers are written and read from the same side. DVDs can be double SIDED and double LAYERED! There can be a semi-transparent layer per side. Depending on the focus of the laser beam, it can either read the main layer or the semi-transparent one. So a DVD can have up to 4 data layers. Most DVDs are single sided but often double layered. The problem is that a player needs at least 4 seconds to move the laser back to the center and refocus to the new layer. This stops the film for a second or two unless the player can read ahead far enough. Cheap commercial DVDs are usually single layered with low quality which give you broadcast SDTV quality. Some use two layers, one for the main film and the second layer for the menus and extras. High quality movies use both layers for the main film and the film is edited so that the change of layers happen during a black change over in scenes. With an old or cheap player, the time between the scenes is extended but you usually can't notice that there is something unwanted happening. With a modern or expensive player, you won't notice anything except the odd noise from the drive when the laser rushes back to its home position. Double sided DVD are rare since they can't have a label. You usually find them in cheap "whole season in one box" offers and most of them are even single layered since double sided cost less to make than double layered. Double sided AND double layered DVD are very rare. I don't think that I own even a single one of those. |
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Post by c64 on Oct 6, 2015 11:03:19 GMT
The Double Layer technology had lead to the "Super CD".
This one has the main layer right beneath the label and is just like a conventional CD. You can put it into any CD player which can read it just like an ordinary CD.
What makes the disc "super" is a DVD like second layer which is invisible to an ordinary CD player. This one has more capacity (4.7GB instead of 640MB) and is encoded in 1-bit but 1MHz sample rate. This is the highest audio playback standard there is. It also can hold video clips so you can listen to the music in any CD player and watch the music video on your super-CD player.
Super-CD players are very rare, but a few DVD players have super-disc capability although they lack the D/A circuits to make the most of the enhanced sound recording on the disc. So they are only good for watching the music videos.
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Post by c64 on Oct 6, 2015 11:38:53 GMT
If you are going to the commercial "Vast runs" of BIG label (warner brothers Virgin and such labels) of factory produced records, yes. Smaller recording studio's use the burn method. I can see where the confusion lies in this, I thought we were talking abut smaller studio's as we started with home stereo, I hadnt realised we had jumped into the Million Quid range of price?... It depends on the number of copies you need and the quality you want. Small series are burned individually and the label printed by an ink printer. This is a time consuming process although you can buy disc writers and disc labelers with 50 piece magazines and just run them unattended "over night". You can order small series of pressed and professionally print labeled discs. You upload the ISO file and get your discs a day or two later. Those discs look much more professional and in case of hiring a minimum wage worker as a disc jockey for your conventional burner, you break even with less than 100 copies. About 15 years ago, business card shaped discs were state of the art. The top was printed like a business card and you could pay it in a CD/DVD drive. Those could hold a business catalogue or presentation of 12MB in size. You can still get them but who has still a CD/DVD drive in his portable computer? So handing them out on trade shows has no point any more since you have to take them back to your company and then look for a drive to play them. Instead, business cards with QR codes are used so you can watch content of any size on your tablet or smart phone while still on the trade show. I have questioned the rarity of the double-side disks, especially in games consuls, and it all hinges on "Confusion". To start with, the extra cost to "Flip the disk" to write the other side was put into question. Fist it has to be ejected spun and cooled if its a burn process. If its a pressing process, the disk has to be made thicker. The number of failed pressings and failed burnings doubles, then quadruples, as perfectly good side A's get ruined by "coaster" side B's, and vice versa, and then the verifying process done after the two sides have finalised, picks up one or the other?... Cost wise, its easier and cheaper to produce double-disks with disk 1 and disk 2 written on the label. Also end users complained about not being able to read the label and putting the disk in upside down by mistake. End user prefers a double disk to a single double sided disk.,... Also some machines refused to take the extra thick disks. Not at all! Just put an old DVD-R into hot water to melt the paint between the layers. You get two discs of less than half the thickness (paint gone). If you put a DL DVD-R in hot water, you get one disc slightly less than half the original thickness and two less than ¾ thick discs. Each layer is pressed individually and then the whole thing is sandwiched to a DVD. Of course it takes more effort to make more layers. And you are correct, a DL or 2-sided or 2-sided DL costs more than pressing several 1-sided SL discs. But we are talking about 3 cents per layer versus 5 cents a simple disc. The major costs come from the packing and shipping. You need to design more labels, you need to print different labels and you need a box holding more disc which costs a lot more money and you have more weight to ship. The cheapest method to ship twice the amount of data is the double sided, single layered disc. No label, no extra weight and no extra packing. But since it is ugly and the customers wants a pretty label, the single sided, double layered disc is usually used instead. Also even if burned, a $15,000 disc burner with a 100 piece magazine (and label printer for single sided) can burn both sides at the same time. It just writes the backside in reverse, starting from the outside in. Those things are used for small software companies which often update their software so ordering 1000 pressed discs won't do if they are obsolete faster than they are sold. That's why online updates are the method of choice, e.g. Steam. You get the obsolete game data and a program that updates the data while installing over the net. In case of Half Life 2, ¾ of your "orange box" is now replaced online so there is no point in even installing everything right from your disc, just install Steam, type in the code from the box and download the entire stuff online. |
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Post by c64 on Oct 6, 2015 12:01:27 GMT
The file may be called an "Image", but its still "Burned on via laser". it has the file type .iso... Form File type ISO 9660 which is a file "type", such as FAT-32 or NTFS are also file "Types" The image file is a complete file including directory and finalising that is put on all in one go, without having to bother the processing of the computer or equipment to create a directory, which in burning a normal list of tracks to put on, has to be done by the burning process. More or less, its seen as a "Single track" from start to finish. This takes less space, as the computer doesnt have to create a directory tree to hold that information, and doesnt have to create the directory, nor the finalising file. Its a form of "Zip file". It takes less handling in transfer. Not at all! The sole purpose of the iso image is to make an exact duplicate of the disc structure. It is NOT smaller, it contains all the error checking data required for a CD or DVD. A disc can never be perfectly made nor read, there are always errors on the disc and read errors on top. Up to 15% of the read data is wrong! In case of an audio CD, a minor error check is required since the player can reconstruct errors from the audio pattern and fill in the gaps where the error correction fails. A data CD is different, lost bits can't be restored so over ¼ of the data on the disc is "overhead" for data correction. That's why your burning software differs between "music" and "data" (or mixed mode) projects. "music" tracks have no directory structures and a minor error correction overhead. "Data" tracks do have directories and extended data correction. Just making a copy of the actual data in individual files will give you a perfect reproduction of the content. But burning it back, you need to select which file goes on which track and you need to know if this track is data or music. Also in case of data, each time you switch between reading files, the laser must run back to the start of the disc, read the disc table and then look for the proper track and find the directory inside the track before it can start to look for the file content. Also the different circumferences of the disc give you different reading speeds. So to speed up reading, you put all files which are read the most near the start of the disc so you loose less time finding the files. Rarely used files should be put more to the outside of the disc in favour to files which are read more often. And big files should also be on the outside since the greater circumference gives you more data per revolution so you can read this file faster. And this is what the ISO file is for. An exact reproduction of the disc which has its file positions on the disc optimized for faster access and faster reading while playing. This isn't so important any more since everything is installed on a HDD nowadays but it was highly important for the Playstation and other disc based video game consoles and early PC games playing their data directly from CD/DVD while playing. |
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Post by the light works on Oct 6, 2015 14:18:33 GMT
If you are going to the commercial "Vast runs" of BIG label (warner brothers Virgin and such labels) of factory produced records, yes. Smaller recording studio's use the burn method. I can see where the confusion lies in this, I thought we were talking abut smaller studio's as we started with home stereo, I hadnt realised we had jumped into the Million Quid range of price?... I have questioned the rarity of the double-side disks, especially in games consuls, and it all hinges on "Confusion". To start with, the extra cost to "Flip the disk" to write the other side was put into question. Fist it has to be ejected spun and cooled if its a burn process. If its a pressing process, the disk has to be made thicker. The number of failed pressings and failed burnings doubles, then quadruples, as perfectly good side A's get ruined by "coaster" side B's, and vice versa, and then the verifying process done after the two sides have finalised, picks up one or the other?... Cost wise, its easier and cheaper to produce double-disks with disk 1 and disk 2 written on the label. Also end users complained about not being able to read the label and putting the disk in upside down by mistake. End user prefers a double disk to a single double sided disk.,... Also some machines refused to take the extra thick disks. actually, the scaling between "short run burned discs" and "large scale mass produced discs" is smaller than you think - the price point comes in at about 200 copies, lower if you count the time it takes to load the machines. |
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Post by the light works on Oct 6, 2015 14:23:12 GMT
you haven't seen an all-in-one box set system, have you? Yes, this box is called Smartphone or media server playing to any TV and amp in your network by the DLNA or UPnP standard. no, a box set is a "system" that all comes packed in one box. it costs about the price of one component of a better grade system. |
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Post by GTCGreg on Oct 6, 2015 14:40:55 GMT
no, a box set is a "system" that all comes packed in one box. it costs about the price of one component of a better grade system. I've seen "one box" TV's that have everything in them including WiFi, Bluetooth, and a DVD player. One of my main concerns about such a system is you know what is going to go wacky first. The DVD player. |
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Post by the light works on Oct 6, 2015 14:46:08 GMT
no, a box set is a "system" that all comes packed in one box. it costs about the price of one component of a better grade system. I've seen "one box" TV's that have everything in them including WiFi, Bluetooth, and a DVD player. One of my main concerns about such a system is you know what is going to go wacky first. The DVD player. right, one box TVs are great for limited application, but there's been a few applications where it really would have simplified the installation. of course, if you made it modular, like, say, putting in a laptop DVD drive for the DVD player, it would solve the problem of the DVD player failing - you just eject it and slide in a new drive. |
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Post by GTCGreg on Oct 6, 2015 16:06:17 GMT
I've seen "one box" TV's that have everything in them including WiFi, Bluetooth, and a DVD player. One of my main concerns about such a system is you know what is going to go wacky first. The DVD player. right, one box TVs are great for limited application, but there's been a few applications where it really would have simplified the installation. of course, if you made it modular, like, say, putting in a laptop DVD drive for the DVD player, it would solve the problem of the DVD player failing - you just eject it and slide in a new drive. But that would take an extra 25 cents in parts. Unfortunately, serviceability isn't very high on consumer electronics design criteria nowadays. |
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Post by the light works on Oct 7, 2015 1:09:40 GMT
right, one box TVs are great for limited application, but there's been a few applications where it really would have simplified the installation. of course, if you made it modular, like, say, putting in a laptop DVD drive for the DVD player, it would solve the problem of the DVD player failing - you just eject it and slide in a new drive. But that would take an extra 25 cents in parts. Unfortunately, serviceability isn't very high on consumer electronics design criteria nowadays. That's like saying Macintosh compatibility isn't very high on Bill Gates' design criteria, nowadays. |
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Post by GTCGreg on Oct 7, 2015 1:23:19 GMT
That's like saying Macintosh compatibility isn't very high on Bill Gates' design criteria, nowadays. Or like saying Apple allowing their OS to be used on non-Apple computers. That would put MS out of business overnight. Of course, it would probably put Apple out of business also as no one would buy their over priced hardware. |
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Post by the light works on Oct 7, 2015 1:46:19 GMT
That's like saying Macintosh compatibility isn't very high on Bill Gates' design criteria, nowadays. Or like saying Apple allowing their OS to be used on non-Apple computers. That would put MS out of business overnight. Of course, it would probably put Apple out of business also as no one would buy their over priced hardware. Apple has always been a little more proud of their hardware than I have been. |
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Post by silverdragon on Oct 7, 2015 7:57:14 GMT
Do the comparison.
Take a directory that has all the data you wish to put on one disk, including the temp.file where all that data is collated to do the burn, see how much space is reserved for that directory, and compare it to the ISO image of that directory.
Add in "lead in and lead out" data.
If its is not "smaller" why do ISO images take a hell of a lot less time to download than "Full directories"
It is not a literal "Zip file" compression and all, its a file where all the waste space left on the disk for file CHANGES have been removed.
As in, all files on a hard drive have a something like 5 to 10% (dependant on file size) "Gap" between that file and the next to allow for minor changes to that file to be done without having to lift the whole file and move it "Elsewhere" because it no longer fits that gap.
(Note a direct "File size" comparison will show exact same file size, its the space on the disk that that file occupies here that is smaller...)
The file is also optimized for music tracks where the WHOLE FILE is sequential for each track so the player doesnt have to seek back and forth between tracks/sectors in the middle of a song.
ISO images are made when the disk image is "Finalised", there needs to be no spaces at all for changes, therefore, the spaces are removed.
At this point, its wise to mention, music files are different than game files.
Music files are sequential from centre of disk outwards, track by track, the reverse of LP tracks.
To know how much, take this whole post and take out all the spaces between words?... if the spaces between words were half the size, could you still read it?.. if they were a quarter of the size, could you still read it?.. if the spaces between letters were treated the same way could you still read it?...
If all the space between the end of this sentence and the next paragraph were to go, would you still be able to read it?.....
The post as you read it now sort of matches how files are stored on a Hard drive, with spaces in-between.
Take the spaces out, and you get more or less (Simplified version for explanation) what an ISO image is.
I am of course over simplifying this "so even a child of ten" reading this thread may understand...
On compression, I can show you a picture here that you will be able to make sense of, than put it as the RAW image from my camera.
The difference in physical size will be exactly the same.
The difference between .jpg and .CRW (Canon Raw) is a world apart, and can be from kilobytes to megabytes, 300 k to 20meg difference.
But the same picture, and I doubt you will be able to see the difference...
Except you may get a prohibition from the site hosting it of file size too large.
How can the same thing have so MUCH difference?..
Compression.
What is that compression?..
An art form.
In the middle you have .TIF files.
In a nutshell, an Image file is an exact copy of what will be written to the CD/DVD.
Instead of your Burning software having to create another temp directory that it can read from start to finish during the burning process which makes it a quicker burn as it doesnt have to hunt all over the disk, it reads that exact information from the .ISO file.
That .ISO file is an exact copy of the temp file that has been created at some point to create the disk.
Instead of writing that to disk, the Burning software has created a single file that is used in all burning processes of that disk.
It saves time, and uses less space.
Burning processes MUST be a continuous process that does not stop when the disk reaches speed.
If it does stop, that how you get a coaster.
Therefore, there is no error checking whilst burning is in process...
It has done that already when doing the temp file.
Therefore having a temp file that is already error checked ?... saves time and space.
That is what an ISO file image is.
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Post by silverdragon on Oct 7, 2015 8:00:10 GMT
Or like saying Apple allowing their OS to be used on non-Apple computers. That would put MS out of business overnight. Of course, it would probably put Apple out of business also as no one would buy their over priced hardware. Apple has always been a little more proud of their hardware than I have been. The difference is Ford or Dodge, either one or the other, some people may say.... But those in the opposing camp may say..... I cant say one is better "All round" than the other, because that just isnt true. One is better than graphics on the other, but then an O/S change may reverse that. |
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Post by the light works on Oct 7, 2015 13:08:04 GMT
Apple has always been a little more proud of their hardware than I have been. The difference is Ford or Dodge, either one or the other, some people may say.... But those in the opposing camp may say..... I cant say one is better "All round" than the other, because that just isnt true. One is better than graphics on the other, but then an O/S change may reverse that. more at Jaguar or Morgan. |
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