Re: New *ist D review - Imaging Resource
is it worth doing it for the camera's preview display? since the camera supports discrete zooming and panning at a fairly fine number of levels, i think it decompresses the entire image into a buffer and uses hardware resampling to show the image. Herb... - Original Message - From: "Peter Loveday" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, April 02, 2004 10:01 PM Subject: Re: New *ist D review - Imaging Resource > Actually, there are ways to do things like this. It is very common for > applications to read every 8th pixel of a JPEG to make a thumbnail, or > display a rough image quickly. > > Due to the way JPEG compression works, by doing DCT based compression on 8x8 > blocks, a value for each 8th pixel is actually present. This is commonly > called the "DC component" for the block. It is usually in YUV colourspace, > of course, so a conversion needs to be done to RGB, but thats trivial.
Re: New *ist D review - Imaging Resource
Actually, there are ways to do things like this. It is very common for applications to read every 8th pixel of a JPEG to make a thumbnail, or display a rough image quickly. Due to the way JPEG compression works, by doing DCT based compression on 8x8 blocks, a value for each 8th pixel is actually present. This is commonly called the "DC component" for the block. It is usually in YUV colourspace, of course, so a conversion needs to be done to RGB, but thats trivial. Love, Light and Peace, - Peter Loveday Director of Development, eyeon Software - Original Message - From: "Herb Chong" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, April 03, 2004 9:40 AM Subject: Re: New *ist D review - Imaging Resource > JPEG compresses data. you don't know what the nth pixel is until you > decompress enough of the file to find it. some other formats do row level > lossless compression, so you can figure out which row to decompress, but > that is all. > > Herb > - Original Message - > From: "vr" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Friday, April 02, 2004 4:59 AM > Subject: Re: New *ist D review - Imaging Resource > > > > how is that? > > you can give an order to address and read every 4th pixel from file.. > > > > what do you think modern databases work like where ypou can get desired > > bits from huge file in seconds if the file is indexed?? > > > > though to be faster or more reasonable compared to readin everything the > > gap should not be every 4th pixel, but much wider.. > > >
Re: New *ist D review - Imaging Resource
> > > > John Francis wrote: > > > > not to display some of the pixels if they were available, and there's > > no reasonable way to get some of the pixels from an image without > > getting all of them (except, as noted, if it were a progressive JPEG). > > > > how is that? > you can give an order to address and read every 4th pixel from file.. No you can't. You have to read all the pixels into memory. If you then choose to ignore 3/4 of them that's your choice, but you've still transferred all of them over the slow datapath (external media to local memory), which is where most of the time is spent. (You can, of course, start reading at the top row of your zoomed-in view of the image, and stop reading once you've got to the bottom row. But you're going to have to read all the pixels on each of those rows, including the ones off-sceen to the left or right of your chosen view) > what do you think modern databases work like where ypou can get desired > bits from huge file in seconds if the file is indexed?? Database indices do a lot more than just calculate record offsets. But they have a memory-resident table that tells them which of the blocks to read in from the (slow) external media in order to get the record they want. The index just stops them having to read every one of the many millions of records in sequence (and perform certain simple checks); once they get a record they will read all of it. > though to be faster or more reasonable compared to readin everything the > gap should not be every 4th pixel, but much wider.. Yes. Much, *much* wider. Larger than the block size of the storage media, which is never going to be the case for these image files. > i guess > > viljar
Re: New *ist D review - Imaging Resource
In Photoshop you are up to 5 interlaced images. Well version 5.5 at least. Rob Brigham wrote: Yeah, but jpg doesn't record pixels like that. What you suggest could work with a bitmap, but a jpg is different. Don't ask me the techie details, but I think of it as recording a start position, colour value, then the number of adjacent pixels of that colour. So building up a picture means it is necessary to decode the whole file. Progressive jpgs obviously work a bit differently - perhaps recrding 2 images with alternate rows in each image, then interlacing them? Anyways, what you say is not easy or perhaps even possible for a standard jpg... -Original Message- From: vr [mailto:[EMAIL PROTECTED] Sent: 02 April 2004 11:00 To: [EMAIL PROTECTED] Subject: Re: New *ist D review - Imaging Resource John Francis wrote: not to display some of the pixels if they were available, and there's no reasonable way to get some of the pixels from an image without getting all of them (except, as noted, if it were a progressive JPEG). how is that? you can give an order to address and read every 4th pixel from file.. what do you think modern databases work like where ypou can get desired bits from huge file in seconds if the file is indexed?? though to be faster or more reasonable compared to readin everything the gap should not be every 4th pixel, but much wider.. i guess viljar
RE: New *ist D review - Imaging Resource
Yeah, but jpg doesn't record pixels like that. What you suggest could work with a bitmap, but a jpg is different. Don't ask me the techie details, but I think of it as recording a start position, colour value, then the number of adjacent pixels of that colour. So building up a picture means it is necessary to decode the whole file. Progressive jpgs obviously work a bit differently - perhaps recrding 2 images with alternate rows in each image, then interlacing them? Anyways, what you say is not easy or perhaps even possible for a standard jpg... > -Original Message- > From: vr [mailto:[EMAIL PROTECTED] > Sent: 02 April 2004 11:00 > To: [EMAIL PROTECTED] > Subject: Re: New *ist D review - Imaging Resource > > > > > John Francis wrote: > > > > not to display some of the pixels if they were available, > and there's > > no reasonable way to get some of the pixels from an image without > > getting all of them (except, as noted, if it were a > progressive JPEG). > > > > how is that? > you can give an order to address and read every 4th pixel from file.. > > what do you think modern databases work like where ypou can > get desired > bits from huge file in seconds if the file is indexed?? > > though to be faster or more reasonable compared to readin > everything the > gap should not be every 4th pixel, but much wider.. > > i guess > > viljar > > > > >
Re: New *ist D review - Imaging Resource
John Francis wrote: not to display some of the pixels if they were available, and there's no reasonable way to get some of the pixels from an image without getting all of them (except, as noted, if it were a progressive JPEG). how is that? you can give an order to address and read every 4th pixel from file.. what do you think modern databases work like where ypou can get desired bits from huge file in seconds if the file is indexed?? though to be faster or more reasonable compared to readin everything the gap should not be every 4th pixel, but much wider.. i guess viljar
Re: New *ist D review - Imaging Resource
On 1 Apr 2004 at 12:37, Keith Whaley wrote: > There's no replacing of one low-resolution image with another high res > image. It's a filling in of pixel information left out of the initial pass. It sounds like the embedded jpeg may be a variation on progressive jpeg which does in fact display progressively higher density jpg images as the file loads. http://www.faqs.org/faqs/jpeg-faq/part1/section-11.html Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: New *ist D review - Imaging Resource
Bucky wrote: When one previews the picture in the on-camera screen, you will notice that the camera apparently loads a small image first. Then, if you keep that image in the monitor for a few seconds, it is substituted with a larger one. You can see the effect when you call up a preview of a shot with a detailed pattern such as ripples on water - after several seconds you will see a noticeable shift in the pattern when the second (presmably larger image suitable for zooming into) is loaded and substituted. Just my personal observation. I think what's happening is, a lot of pixels are loaded up to the display, but perhaps only 40% of them, primarily to get something that looks like an image displayed. That keeps the viewer patient, while he's waiting for the whole thing to display, at the full resolution intended. It's just a ploy to keep the viewer happy. Soon the full photo/image will be displayed, but if he had to wait for the entire thing to load from the start, he might go elsewhere! First pass, maybe 30-40% of the detail of the image, but full size (4x6" or whatever...) Second pass, fill in the missing pixels, but a little more slowly. Since the viewer has a pretty good idea of what the image is going to look like, he's far more patient and can wait for it to fill-in. There's no replacing of one low-resolution image with another high res image. It's a filling in of pixel information left out of the initial pass. keith whaley
Re: New *ist D review - Imaging Resource
197.5 MB total On Thu, 2004-04-01 at 01:40, William M Kane wrote: > The question is what speed DID you confirm? I believe that the > original article spoke of an unusually high speed for USB 1.1, but > didn't claim it was of USB 2.0 caliber . . . > > . . . so the question becomes, How many MB were the 15 RAW files? > > IL Bill > On Wednesday, March 31, 2004, at 03:19 PM, Frits Wüthrich wrote: > > > I just ran a test and I can NOT confirm the USB2 speed for the *ist D > > connected to a PC. > > This is what I did: > > I connected the *ist D with my PC by means of the Pentax supplied USB > > cable, and copied all 15 RAW images that I had on the flash card to a > > folder on a drive of my PC. > > That took about 3 minutes and 30 seconds. > > Then I removed the flash card and put it in a USB2 6 in 1 card reader, > > and now using the same 15 images to copy to the same drive in another > > folder, I found a time of 1 minute and 2 seconds. So the reader was 3.5 > > times faster. > > I have the firmware version 1.11 on my *ist D. > > > > > > > > > > On Wed, 2004-03-31 at 22:26, Sylwester Pietrzyk wrote: > >> On 2004-03-31, at 14:40, Mark Roberts wrote: > >> > >>> "While the manual claims that the *ist D only supports the USB v1.1 > >>> interface standard, my own tests seemed to show that it's actually > >>> running at USB v2.0 speeds. I clocked its download speed at 1963 > >>> KB/second with a Lexar 24x memory card, connected to my Sony VAIO > >>> Windows XP workstation. (2.4 GHz Pentium IV processor, 512 MB of > >>> RAM.) > >>> This is quite fast: Cameras with USB v1.1 interfaces top out at a > >>> little > >>> over 600 KB/second. I've seen USB 2.0-equipped cameras move data as > >>> quickly as several MB/second, but the *ist D's download speed is > >>> faster > >>> than average, even among cameras with USB 2.0 interfaces." > >> > >> That's indeed very interesting. I just bought USB 2 card for my Mac - > >> will try it :-) > >> > >> Best regards > >> Sylwek > >> > > -- > > Frits Wüthrich <[EMAIL PROTECTED]> > > > > -- Frits Wüthrich <[EMAIL PROTECTED]>
Re: New *ist D review - Imaging Resource
>> Maybe it's a stealth upgrade to newer *ist-D's << I doubt that, for two reasons: 1) I emailed the Image Resource reviewer a few weeks ago asking if he was ever going to review the *ist D. He replied that he'd started an *ist D review a long time ago but had been unable to find the time to finish it. So, if there had been a recent slipstream to USB 2.0, he probably wouldn't have it. 2) My *ist D arrived from Adorama just 6 days ago, so if there had been a recent slipstream that any customers had yet, I'd probably have it too. But here are my numbers, using a Lexar WA 40X 1GB card: *ist D on a USB 1.1 port (built onto motherboard): 0.834 MB/Second (No message from Windows XP suggesting I use a USB 2.0 port for it) *ist D on a USB 2.0 port (on an add-on card): 0.824 MB/Second Lexar USB 2.0 Card Reader on the USB 2.0 port: 3.147 MB/Second That's consistent with what others here have reported. The reviewer's time seems to be at least twice as fast as any of ours. Greg > Maybe it's a stealth upgrade to newer *ist-D's - my *ist-D hooked directly > to the PC and my USB 1.1 card reader both take about 20 minutes to > download > 1 gig of data. My X-Drive II takes only ~5 minutes for the same transfer > using USB 2. The card in the X-Drive reader is somewhat faster than USB > 1.1 > at ~15 minutes - don't know what conectivity is in the X-Drive. > > - MCC > > At 07:40 AM 3/31/2004 -0500, you wrote: >>"Greg Lovern" <[EMAIL PROTECTED]> wrote: >> >> >New review of the *ist D at Imaging Resource: >> > >> > http://www.imaging-resource.com/PRODS/ISTD/ISTDA.HTM >> > >> >Very positive; maybe the most positive I've read. >> >>Now *here's* an interesting excerpt from that review: >> >>"While the manual claims that the *ist D only supports the USB v1.1 >>interface standard, my own tests seemed to show that it's actually >>running at USB v2.0 speeds. I clocked its download speed at 1963 >>KB/second with a Lexar 24x memory card, connected to my Sony VAIO >>Windows XP workstation. (2.4 GHz Pentium IV processor, 512 MB of RAM.) >>This is quite fast: Cameras with USB v1.1 interfaces top out at a little >>over 600 KB/second. I've seen USB 2.0-equipped cameras move data as >>quickly as several MB/second, but the *ist D's download speed is faster >>than average, even among cameras with USB 2.0 interfaces." >> >>-- >>Mark Roberts >>Photography and writing >>www.robertstech.com > > - > > Mark Cassino Photography > > Kalamazoo, MI > > http://www.markcassino.com > > - > > >
RE: New *ist D review - Imaging Resource
When one previews the picture in the on-camera screen, you will notice that the camera apparently loads a small image first. Then, if you keep that image in the monitor for a few seconds, it is substituted with a larger one. You can see the effect when you call up a preview of a shot with a detailed pattern such as ripples on water - after several seconds you will see a noticeable shift in the pattern when the second (presmably larger image suitable for zooming into) is loaded and substituted. Just my personal observation. > -Original Message- > From: John Francis [mailto:[EMAIL PROTECTED] > Sent: 31-Mar-04 20:50 > To: [EMAIL PROTECTED] > Subject: Re: New *ist D review - Imaging Resource > > > > > > On 31 Mar 2004 at 22:06, William Robb wrote: > > > > > I thought RAW files were kinda fixed size. > > > > I don't know if you recall but John did mentioned a few weeks > back that they > > also include an embedded jpg file. From my experience they vary > in size from > > around 12,750kB to 14,500kB. > > Several JPEG images, actually. So far I've found a 160 x 120 thumbnail, > a 640 x 480 image that's presumably used in Photo Browser, and a full- > size (3008 x 2008) version. I *think* that's all ... > > >
Re: New *ist D review - Imaging Resource
> > On 31 Mar 2004 at 22:06, William Robb wrote: > > > I thought RAW files were kinda fixed size. > > I don't know if you recall but John did mentioned a few weeks back that they > also include an embedded jpg file. From my experience they vary in size from > around 12,750kB to 14,500kB. Several JPEG images, actually. So far I've found a 160 x 120 thumbnail, a 640 x 480 image that's presumably used in Photo Browser, and a full- size (3008 x 2008) version. I *think* that's all ...
Re: New *ist D review - Imaging Resource
On 31 Mar 2004 at 23:19, Frits Wüthrich wrote: > I just ran a test and I can NOT confirm the USB2 speed for the *ist D > connected to a PC. Nor me. I loaded a file of almost 1GB on my Ridata 52x Pro card and found the following Card read results: X-Drive II via USB2 (add on PCI Via card) 3668kB/s *ist D via USB2 (add on PCI Via card) 912kB/s *ist D via USB1.1 (embedded on m/b) 932kB/s The USB 1.1 serial data transfer speed is quoted as 12Mb/s so in each case the *ist D transfer speed is within that specification and what I would expect including serial transfer protocol overheads. Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: New *ist D review - Imaging Resource
On 31 Mar 2004 at 22:06, William Robb wrote: > I thought RAW files were kinda fixed size. I don't know if you recall but John did mentioned a few weeks back that they also include an embedded jpg file. From my experience they vary in size from around 12,750kB to 14,500kB. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: New *ist D review - Imaging Resource
- Original Message - From: "William M Kane" Subject: Re: New *ist D review - Imaging Resource > The question is what speed DID you confirm? I believe that the > original article spoke of an unusually high speed for USB 1.1, but > didn't claim it was of USB 2.0 caliber . . . > > . . . so the question becomes, How many MB were the 15 RAW files? I thought RAW files were kinda fixed size. William Robb
Re: New *ist D review - Imaging Resource
my Lexar Media Firewire card takes just over 3 minutes for a full 1G card. Herb - Original Message - From: "Mark Cassino" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, March 31, 2004 6:57 PM Subject: Re: New *ist D review - Imaging Resource > Maybe it's a stealth upgrade to newer *ist-D's - my *ist-D hooked directly > to the PC and my USB 1.1 card reader both take about 20 minutes to download > 1 gig of data. My X-Drive II takes only ~5 minutes for the same transfer > using USB 2. The card in the X-Drive reader is somewhat faster than USB 1.1 > at ~15 minutes - don't know what conectivity is in the X-Drive.
Re: New *ist D review - Imaging Resource
Maybe it's a stealth upgrade to newer *ist-D's - my *ist-D hooked directly to the PC and my USB 1.1 card reader both take about 20 minutes to download 1 gig of data. My X-Drive II takes only ~5 minutes for the same transfer using USB 2. The card in the X-Drive reader is somewhat faster than USB 1.1 at ~15 minutes - don't know what conectivity is in the X-Drive. - MCC At 07:40 AM 3/31/2004 -0500, you wrote: "Greg Lovern" <[EMAIL PROTECTED]> wrote: >New review of the *ist D at Imaging Resource: > > http://www.imaging-resource.com/PRODS/ISTD/ISTDA.HTM > >Very positive; maybe the most positive I've read. Now *here's* an interesting excerpt from that review: "While the manual claims that the *ist D only supports the USB v1.1 interface standard, my own tests seemed to show that it's actually running at USB v2.0 speeds. I clocked its download speed at 1963 KB/second with a Lexar 24x memory card, connected to my Sony VAIO Windows XP workstation. (2.4 GHz Pentium IV processor, 512 MB of RAM.) This is quite fast: Cameras with USB v1.1 interfaces top out at a little over 600 KB/second. I've seen USB 2.0-equipped cameras move data as quickly as several MB/second, but the *ist D's download speed is faster than average, even among cameras with USB 2.0 interfaces." -- Mark Roberts Photography and writing www.robertstech.com - Mark Cassino Photography Kalamazoo, MI http://www.markcassino.com -
Re: New *ist D review - Imaging Resource
Which means they were moving at .92 MB/s with the USB cable connected to the camera. and 3.14 MB/s with the USB 2.0 6 in 1 reader. On Wednesday, March 31, 2004, at 05:49 PM, alex wetmore wrote: On Wed, 31 Mar 2004, William M Kane wrote: . . . so the question becomes, How many MB were the 15 RAW files? RAW files are 13mb. 13 * 15 = 195mb. alex
Re: New *ist D review - Imaging Resource
On Wed, 31 Mar 2004, William M Kane wrote: > . . . so the question becomes, How many MB were the 15 RAW files? RAW files are 13mb. 13 * 15 = 195mb. alex
Re: New *ist D review - Imaging Resource
On 31 Mar 2004, Frits [ISO-8859-1] Wüthrich wrote: > I just ran a test and I can NOT confirm the USB2 speed for the *ist D > connected to a PC. > This is what I did: > I connected the *ist D with my PC by means of the Pentax supplied USB > cable, and copied all 15 RAW images that I had on the flash card to a > folder on a drive of my PC. > That took about 3 minutes and 30 seconds. > Then I removed the flash card and put it in a USB2 6 in 1 card reader, > and now using the same 15 images to copy to the same drive in another > folder, I found a time of 1 minute and 2 seconds. So the reader was 3.5 > times faster. > I have the firmware version 1.11 on my *ist D. Having a USB 2.0 port in the camera doesn't mean that the camera is going to be as fast as a USB 2.0 reader. In particular the chipset for managing the compact flash card might not be as fast as reading as a USB 2.0 reader would be. Your test shows that the camera did about 0.92mbps over the USB cable. That is faster than most USB 1.1 readers, but I think still slower than the USB 1.1 available bandwidth (1.1mbps, but I don't know how much overhead is taken up by the system). If you have a USB 1.1 hub and plug in a USB 2.0 device you should get a popup from Windows XP which tells you that it woudl be faster to use a USB 2.0 high speed port. I haven't seen this popup with my *ist D, and used to see it all the time with my DSC-F717, so I think that the camera is USB 1.1. alex
Re: New *ist D review - Imaging Resource
I just ran a test and I can NOT confirm the USB2 speed for the *ist D connected to a PC. This is what I did: I connected the *ist D with my PC by means of the Pentax supplied USB cable, and copied all 15 RAW images that I had on the flash card to a folder on a drive of my PC. That took about 3 minutes and 30 seconds. Then I removed the flash card and put it in a USB2 6 in 1 card reader, and now using the same 15 images to copy to the same drive in another folder, I found a time of 1 minute and 2 seconds. So the reader was 3.5 times faster. I have the firmware version 1.11 on my *ist D. On Wed, 2004-03-31 at 22:26, Sylwester Pietrzyk wrote: > On 2004-03-31, at 14:40, Mark Roberts wrote: > > > "While the manual claims that the *ist D only supports the USB v1.1 > > interface standard, my own tests seemed to show that it's actually > > running at USB v2.0 speeds. I clocked its download speed at 1963 > > KB/second with a Lexar 24x memory card, connected to my Sony VAIO > > Windows XP workstation. (2.4 GHz Pentium IV processor, 512 MB of RAM.) > > This is quite fast: Cameras with USB v1.1 interfaces top out at a > > little > > over 600 KB/second. I've seen USB 2.0-equipped cameras move data as > > quickly as several MB/second, but the *ist D's download speed is faster > > than average, even among cameras with USB 2.0 interfaces." > > That's indeed very interesting. I just bought USB 2 card for my Mac - > will try it :-) > > Best regards > Sylwek > -- Frits Wüthrich <[EMAIL PROTECTED]>
Re: New *ist D review - Imaging Resource
On 2004-03-31, at 14:40, Mark Roberts wrote: "While the manual claims that the *ist D only supports the USB v1.1 interface standard, my own tests seemed to show that it's actually running at USB v2.0 speeds. I clocked its download speed at 1963 KB/second with a Lexar 24x memory card, connected to my Sony VAIO Windows XP workstation. (2.4 GHz Pentium IV processor, 512 MB of RAM.) This is quite fast: Cameras with USB v1.1 interfaces top out at a little over 600 KB/second. I've seen USB 2.0-equipped cameras move data as quickly as several MB/second, but the *ist D's download speed is faster than average, even among cameras with USB 2.0 interfaces." That's indeed very interesting. I just bought USB 2 card for my Mac - will try it :-) Best regards Sylwek
