sdai Posted October 25, 2006 Share #141 Posted October 25, 2006 Advertisement (gone after registration) Exiftool output from a Canon cr2 file shows the following: Bits Per Sample : 8 8 8 I'm not sure what that is, Jon ... but a quick run against a D2X file shows exactly that it has 12-bit color depth: ExifTool Version Number : 6.48 File Name : DSC_0200.nef File Type : NEF Make : NIKON CORPORATION Camera Model Name : NIKON D2X Software : Ver.2.00 Subfile Type : Full-resolution Image Image Width : 4288 Image Height : 2848 Bits Per Sample : 12 Compression : Nikon NEF Uncompressed ... Link to post Share on other sites More sharing options...
Advertisement Posted October 25, 2006 Posted October 25, 2006 Hi sdai, Take a look here M8-why 10MB-vs-DMR 20MB . I'm sure you'll find what you were looking for!
blado Posted October 25, 2006 Share #142 Posted October 25, 2006 Yes, I think there's more to the exif tag. From the exif spec at: http://www.exif.org/Exif2-2.PDF note this line: Number of bits per component BitsPerSample 258 102 SHORT 3 and this line from a sample at: EXIF Data Bits Per Sample 0102 8 8 8 unsigned short 3 There it is again; 3 components for tag id 0102. The M8 and Nikon files reporting one number vs Canon's three. The definition in the pdf is: BitsPerSample The number of bits per image component. In this standard each component of the image is 8 bits, so the value for this tag is 8. See also SamplesPerPixel. In JPEG compressed data a JPEG marker is used instead of this tag. Tag = 258 (102.H) Type = SHORT Count = 3 Default = 8 8 8 Oh well. All way beyond me! Link to post Share on other sites More sharing options...
Andrej Kolev Posted October 25, 2006 Share #143 Posted October 25, 2006 More thoughts: Lets take Kodak KAF 10500, sensor used in M8. Look to Specs: Linear dynamic range = 71.5 db at temp. 40 C. It means 3 758 levels or 12 bits. Link to post Share on other sites More sharing options...
sdai Posted October 25, 2006 Share #144 Posted October 25, 2006 Jon ... this is all the way beyond me too. If my understanding is correct, BitsPerSample is a value paired with another one called Photometric Interpretation to decode the file. Canon obviously adopted a different class of values where their Photometric Interpretation setting refers to RGB, while the Photometric Interpretation value inside the Leica file and Nikon's NEF files are all set to Color Filter Array. With the Photometric Interpretation set to CFA (Color Filter Array), the BitsPerSample value should be the color depth of the file. Andrej, is this correct? Link to post Share on other sites More sharing options...
Guest guy_mancuso Posted October 25, 2006 Share #145 Posted October 25, 2006 Has anyone bothered to check the specs from the DMR sensor to the M8 sensor they are almost identical or even better the Exif data from a DMR to the M8 and look at that. There like kissing cousins . Link to post Share on other sites More sharing options...
sdai Posted October 25, 2006 Share #146 Posted October 25, 2006 Guy, you'd have never imagined that the best part is: I HAVE A DMR!!! :D ExifTool Version Number : 6.48 File Name : L2067892.dng File Size : 19 MB File Modification Date/Time : 2006:10:25 00:35:45 File Type : DNG MIME Type : image/x-raw X Resolution : 72 Y Resolution : 72 Resolution Unit : inches Software : Rev 154(0.13.8.13.28.2.2) Modify Date : 2006:10:24 11:49:20 Subfile Type : Full-resolution Image Image Width : 3884 Image Height : 2592 Bits Per Sample : 16 Compression : Uncompressed Photometric Interpretation : Color Filter Array Strip Offsets : 194048 Samples Per Pixel : 1 Rows Per Strip : 2592 Strip Byte Counts : 20134656 Planar Configuration : Chunky CFA Repeat Pattern Dim : 2 2 CFA Pattern 2 : 0 1 1 2 Default Crop Origin : 4 4 Default Crop Size : 3876 2584 Bayer Green Split : Anti Alias Strength : 0 Version : 3.1 Raw File Name : L2067892.DNG White Balance : As Shot Temperature : 3950 Tint : +12 Auto Exposure : True Exposure : -0.70 Auto Shadows : True Shadows : 4 Auto Brightness : True Brightness : 73 Auto Contrast : True Luminance Smoothing : 0 Color Noise Reduction : 25 Chromatic Aberration R : 0 Chromatic Aberration B : 0 Vignette Amount : 0 Shadow Tint : 0 Red Hue : 0 Red Saturation : 0 Green Hue : 0 Green Saturation : 0 Blue Hue : 0 Blue Saturation : 0 Tone Curve Name : Medium Contrast Tone Curve : 0, 0, 32, 22, 64, 56, 128, 128, 192, 196, 255, 255 Camera Profile : Embedded Has Settings : True Has Crop : False Aperture Value : 3.4 Flash Fired : False Flash Return : No return detection Flash Mode : Unknown Flash Function : True Flash Red Eye Mode : False Serial Number : xxxxxxx Make : Leica Camera AG Camera Model Name : R9 - Digital Back DMR Date/Time Modified : 2006:10:24 11:49:20+02:00 Orientation : Horizontal (normal) Creator Tool : Rev 154(0.13.8.13.28.2.2) Rating : 0 Exposure Time : 1/12 F Number : 3.4 Exposure Program : Program AE ISO : 100 Exif Version : 0220 Date/Time Original : 2006:10:24 11:49:20 Create Date : 2006:10:24 11:49:20 Shutter Speed Value : 0.9 Exposure Compensation : 0 Metering Mode : Multi-segment Light Source : Other Flash : No flash function Focal Length : 0.0mm Color Space : Uncalibrated Contrast : Normal Saturation : Normal Sharpness : Normal Image Unique ID : 0000000000000000004C764900000BA7 DNG Version : 1 0 0 0 Unique Camera Model : Leica DMR Color Matrix 1 : 1.743042 -0.9219971 -0.05395508 -0.4549561 1.333008 0.1290283 -0.09301758 0.2259521 0.7819824 As Shot Neutral : 0.8112498 1 0.6125776 Camera Serial Number : xxxxxxx Maker Note Safety : Safe Raw Data Unique ID : 927BEB514CE8F3D6B8F03D61FA93C172 Aperture : 3.4 CFA Pattern : [Red,Green][Green,Blue] Image Size : 3884x2592 Shutter Speed : 1/12 Focal Length : 0.0mm LV : 7.1 Link to post Share on other sites More sharing options...
Guest guy_mancuso Posted October 25, 2006 Share #147 Posted October 25, 2006 Advertisement (gone after registration) Certainly have good taste. So are the files in question the shipping firmware or the beta stuff, i got lost here was out all day actually shooting , nice change. LOL Link to post Share on other sites More sharing options...
jscottyk Posted October 25, 2006 Share #148 Posted October 25, 2006 Here's something interesting. Checking out these little snips from exiftool results... ...from a 20D .cr2 ExifTool Version Number : 6.49 File Name : _MG_2188.CR2 File Size : 6 MB File Modification Date/Time : 2006:10:24 22:34:08 File Type : CR2 MIME Type : image/x-raw Image Width : 1536 Image Height : 1024 Bits Per Sample : 8 8 8 Compression : JPEG (old-style) ... from the same 20D file converted to .dng ExifTool Version Number : 6.49 File Name : _MG_2188.dng File Size : 5 MB File Modification Date/Time : 2006:10:24 23:34:38 File Type : DNG MIME Type : image/x-raw Strip Offsets : 37348 Rows Per Strip : 171 Strip Byte Counts : 131328 Artist : unknown Image Width : 3596 Image Height : 2360 Bits Per Sample : 16 Compression : JPEG ...from a 5D .cr2 ExifTool Version Number : 6.49 File Name : _MG_9747.CR2 File Size : 11 MB File Modification Date/Time : 2006:09:22 23:53:34 File Type : CR2 MIME Type : image/x-raw Image Width : 2496 Image Height : 1664 Bits Per Sample : 8 8 8 Compression : JPEG (old-style) ... from the same 5D file converted to .dng ExifTool Version Number : 6.49 File Name : _MG_9747.dng File Size : 9 MB File Modification Date/Time : 2006:10:24 23:34:46 File Type : DNG MIME Type : image/x-raw Strip Offsets : 109956 Rows Per Strip : 171 Strip Byte Counts : 131328 Image Width : 4476 Image Height : 2954 Bits Per Sample : 16 Compression : JPEG Link to post Share on other sites More sharing options...
sdai Posted October 25, 2006 Share #149 Posted October 25, 2006 So are the files in question the shipping firmware or the beta stuff, i got lost here was out all day actually shooting , nice change. LOL Not sure if 1.06 will be the shipping firmware but it's definitely the latest known to people on earth. :D Link to post Share on other sites More sharing options...
Guest guy_mancuso Posted October 25, 2006 Share #150 Posted October 25, 2006 I don't think that number would be a shipping version to be honest , it is in nowhere land. They will most likely be like Version 1.0 than the first firmware update would be 1.1. Some kind of beginning . The DMR is version 1.1 than went to 1.2 and 1.3 is next. The 1.6 must be a beta version Link to post Share on other sites More sharing options...
sdai Posted October 25, 2006 Share #151 Posted October 25, 2006 To be dead honest, Guy ... my dealer had never been able to give me a firm date - all he said was wait. Link to post Share on other sites More sharing options...
Andrej Kolev Posted October 25, 2006 Share #152 Posted October 25, 2006 Regrading tags will take a closer look: but I think cr2 is a cannon proprietary format, so they use only a part of exif tags, I found 2 bit depth tags in 350d file, both with 3 values=8. As for DMR I have a support for it in my program so I know that the data is full 16 bit. The sensors a very different I suppose. Try to find DMR specs. You can see from my post with kodak specs M8 actually needs at least 12 bits. It's seems that leica is worried, have you seen thats going on in 'DNG M8 files Online', do you connect it with our 'encoding' talks? Link to post Share on other sites More sharing options...
Andrej Kolev Posted October 25, 2006 Share #153 Posted October 25, 2006 Ok some DMR vs. M8 SNR comparison: M8 Kodak KAF 10500 SNR 71.5 db = 3758 levels = 12 bits DMR Kodak KAF 10010 SNR 67 db = 2238 levels = 12 bits (but more close to 11) According to specs M8 has a great chip saturation level is 1.5 x times more than DMR one, 60000 vs. 40000 (usual value for a 6.8 µm cells) electrons. Dont know how kodak guys managed to get such saturation level. Link to post Share on other sites More sharing options...
sdai Posted October 25, 2006 Share #154 Posted October 25, 2006 Well, I'll have to thank you again for bringing this to my attention, Andrej ... 8 has never been my lucky number. Cheers! Link to post Share on other sites More sharing options...
Andrej Kolev Posted October 25, 2006 Share #155 Posted October 25, 2006 By the way, at this time Pentax scares people with 22-bit quantization. Link to post Share on other sites More sharing options...
Guest guy_mancuso Posted October 25, 2006 Share #156 Posted October 25, 2006 Ok some DMR vs. M8 SNR comparison: M8 Kodak KAF 10500 SNR 71.5 db = 3758 levels = 12 bits DMR Kodak KAF 10010 SNR 67 db = 2238 levels = 12 bits (but more close to 11) According to specs M8 has a great chip saturation level is 1.5 x times more than DMR one, 60000 vs. 40000 (usual value for a 6.8 µm cells) electrons. Dont know how kodak guys managed to get such saturation level. This to me means more Dynamic range from the DMR , reason this is so baffiing to me. So somehow they figured a way to get more range from essential the same sensor. It is a different sensor but is very close to the DMR. that is why i said early there simply is no way to be 8 bit ,more DR and less bits just does not compute real well. Now hell if it is 8 bit and i gain 1.5 stops in DR , damn i may jump all over that. Overall just not make sense not saying your data is wrong or anything like that , there just is no logic to it. But i am far from a engineer . Link to post Share on other sites More sharing options...
Andrej Kolev Posted October 25, 2006 Share #157 Posted October 25, 2006 This to me means more Dynamic range from the DMR , reason this is so baffiing to me. So somehow they figured a way to get more range from essential the same sensor. It is a different sensor but is very close to the DMR. that is why i said early there simply is no way to be 8 bit ,more DR and less bits just does not compute real well. Now hell if it is 8 bit and i gain 1.5 stops in DR , damn i may jump all over that. Overall just not make sense not saying your data is wrong or anything like that , there just is no logic to it. But i am far from a engineer . Guy, I suppose you mean more DR from M8. And difference is not 1.5 stops, as you can see. Also dont forget what at first they get data as 14 bit. Link to post Share on other sites More sharing options...
marknorton Posted October 25, 2006 Share #158 Posted October 25, 2006 Guy, I suppose you mean more DR from M8. And difference is not 1.5 stops, as you can see. Also dont forget what at first they get data as 14 bit. Andrej, Assuming they are using a 14 bit DAC, that maybe just to avoid the 1/2 LSB error they would inevitably get with a 12 bit DAC and they may then be truncating the data to 12 bit after rounding to give a nicely dithered LSB and an accurate measure of the sensor output limited by the sensor's resolution, not the DACs. If that is the case, mapping to 8 bit from 12 bit and back introduces much smaller errors than doing the same with 14 bit. Link to post Share on other sites More sharing options...
Andrej Kolev Posted October 25, 2006 Share #159 Posted October 25, 2006 Mark, I dont know. We only know that 2^14 is the maximum value of back-transformation LUT. But here is some new info - such type of coding was used in imaging modules of several space missions. Some reasearchers stated that such mapping helps to match the quantization level to the photon noise (I've wrote about photon noise before) and helps to distribute quantization errors uniformly across the dynamic range. Also there is some statements that such transform provided a dynamic range of 14 bits in the 8 bits. Will look for more information, but here is the question, if it so simple why other companies dont use it, why they are bothering with a lossless compression, that you think? Link to post Share on other sites More sharing options...
scott kirkpatrick Posted October 25, 2006 Share #160 Posted October 25, 2006 But here is some new info - such type of coding was used in imaging modules of several space missions. Some reasearchers stated that such mapping helps to match the quantization level to the photon noise (I've wrote about photon noise before) and helps to distribute quantization errors uniformly across the dynamic range.Also there is some statements that such transform provided a dynamic range of 14 bits in the 8 bits. Andrej, if you can share the names of the researchers who have looked into the properties of this transformation for imaging data, I'd like to do some reading, too. (I am a physicist first, but make my living in computer science.) Noise in a CCD, in particular, comes in several flavors, some important in the dark, some important at higher temperatures, and some at higher light intensities, so modelling it and its impact on dynamic range is complex, but not impossible to understand. scott Link to post Share on other sites More sharing options...
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