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By: soendoro	Date: 12/06/2003 00:00:00	Points: 50	Status: Answered Quality : Excellent
Hi again... Some question : 1.What application program can produce RAW image, photoshop? Any other? 2. how the file structure in RAW image? 3. I have been try to load a RAW image from photoshop but just work in grayscale.How about the RGB, bitmap,CMYK ? Thx. Soen
By: VGR	Date: 12/06/2003 23:33:00		Type : Answer
RAW is BMP :D

By: VGR	Date: 12/06/2003 23:34:00		Type : Comment
Timeline Buying Guide Side by Side Galleries Forums Search Learn Glossary Feedback Newsletter Links Merchandise About Learn : Glossary : Digital Imaging : RAW Image Format RAW Image Format By Phil Askey The most common image format amongst digital cameras is JPEG, it's a format which produces relatively small files from large amounts of image data by discarding certain information, as JPEG uses a "lossy compression algorithm". The only other common alternative is TIFF, this produces an uncompressed 24-bit per pixel image often in the multiple megabytes, certainly for a 3 megapixel camera in excess of 8 MB per image, not really practical. A little background: each pixel of a CCD can only see one colour, depending on the CFA (colour filter array) placed over the CCD this is either Red/Green/Blue or Cyan/Magenta/Green/Yellow. The cameras internal image processing engine then interpolates colours from the value of neighbouring pixels to calculate a full 24-bit colour for each pixel. RAW is simply the raw data as it comes directly off the CCD, no in-camera processing is performed. Typically this data is 8, 10 or 12 bits per pixel. The advantage being that file sizes are considerably smaller (eg. 2160 x 1440 x 12 bits = 37,324,800 bits = 4,665,600 bytes), the image has not been processed or white balanced which means you can correct the image, and it's a better representation of the "digital negative" captured. The disadvantage is you can't open these image files with a normal photo package without using an "acquire module" (a plugin, typically TWAIN, which can open / process such images). RAW image format has actually been around for quite a while, Canon had a RAW format back in the old PowerShot range and more notably on the Pro 70, all of Kodak's DCS Pro series shoot in a proprietary RAW format (despite the TIFF extension), Nikon's D1 also has a RAW format. Canon have (thankfully) resurrected RAW format for the EOS-D30 and G1. Advantages of RAW format * A true "digital negative", untouched by cameras processing algorithms o No sharpening applied o No gamma or level correction applied o No white balance applied o No colour correction applied * Lossless yet considerably smaller than TIFF * Records data over a wider bit range (typically 10 or 12 bits) than JPEG or 8-bit TIFF Disadvantages of RAW format * Requires proprietary acquire module (typically TWAIN) or plugin to open images * Images can take 20-40 seconds to process on an average machine * No universally accepted RAW standard format, each manufacturer (even each camera) differs Article ©1998-2001 DPReview.Com.

By: VGR	Date: 12/06/2003 23:36:00		Type : Comment
I also found this but I don't know if it's the "RAW format" you wrote about ;-) ERDAS IMAGINE RAW Format DLL One of the most important raster file formats to be supported in the dynamic linked library (DLL) scheme is the generic or "Raw" format. The Raw DLL supports files which are not otherwise supported by a DLL, but which are formatted in such a way that the arrangement of the data may be described by a relatively small number of parameters. The Raw File format is simply another raster format supported under the DLL umbrella, and as such does not need any additional DLL design. However, it does need a well-defined method of describing the image parameters, which is the purpose of this article. The default file filter is "*.raw". A file with a raw extension is presumed to be a header file which indicates the name of the file(s) containing the pixel data and the arrangement of the data within the file(s). Format of the Raw File The raw file is an ASCII file consisting of keywords and associated values. There may be only one keyword per line. Keywords should begin at the first character of a line. Any line which does not begin with a recognized keyword will be ignored; this means that a file may contain comments or other data which is not part of the raw file description. By convention, a comment line is one which begins with the '#' symbol (pound sign). All of the data associated with a keyword must be on the same line with the keyword, unless the continuation character '\' appears at the end of a line. Keywords and strings must be written in uppercase letters, except strings which denote file names. Keywords and associated data are separated by white space (spaces and/or tabs). Keywords may be in any order except the recognition keyword IMAGINE_RAW_FILE, which must appear first. Keywords The only keywords which are required are IMAGINE_RAW_FILE, WIDTH, HEIGHT, and if the data type size is greater than eight bits, BYTE_ORDER. All other keywords are optional and have default values. IMAGINE_RAW_FILE This keyword must be at the very beginning of the file, on a line by itself. WIDTH The number of pixels in the horizontal (x) direction. Must be an integer greater than zero. Required; no default value. HEIGHT The number of pixels in the vertical (y) direction. Must be an integer greater than zero. Required; no default value. NUM_LAYERS The number of layers (channels, bands) in the image. Must be an integer greater than zero. Optional; default value is 1. FORMAT The type of interleaving used in the file. Must be one of the following strings: "BIL" (Band Interleaved By Line), "BIP" (Band Interleaved By Pixel), "BSQ" (Band Sequential), or "TILED" (Tiled or blocked image). Tiled data is presumed to be band sequential within each tile. If the width and/or height of the file is not an even multiple of the tile size, the tiles must be padded with zeros so that all tiles are the same size. The tiles themselves are arranged left to right, top to bottom. For single-layer images, BIL, BIP and BSQ are the same. Optional; default value is "BIL". DATA_TYPE The data type used by the image. Must be one of the following strings: "Ul", "U2", "U4", "U8", "Ul6","Sl6", "U32", "S32", "F32", "F64". Optional; default value is "U8". LAYER_TYPE The layer type used by the image. Must be either "ATHEMATIC" or "THEMATIC". Optional; default value is "ATHEMATIC". BYTE_ORDER For data types of sixteen bits or larger, the ordering of the high and low bytes must be either "MSB" (most-significant-byte first, or Motorola ordering), or "LSB" (least-significant-byte first, or Intel ordering). Required for DATA_TYPE values of U16, S16, U32, S32, F32, and F64; ignored otherwise. PIXEL_FILES The name of the file(s) in which the pixel data reside. For BIL, BIP and Tiled formats, all of the pixel data must reside in the same file. For BSQ formats, each band may reside in a separate file. Optional; defaults to the name of the raw file without the raw extension. If the file does not contain a path part, the same path part as the raw file will be assumed. DATA_OFFSET The number of bytes to be skipped at the beginning of a pixel file. Must be an integer greater than or equal to zero. Optional; defaults to zero. RECORD_SKIP_BYTES The number of bytes skipped between data records. A data record is defined differently depending on the format. For BIL and BSQ images, a data record holds one row of pixels from one layer. For BIP images, a data record holds one row of pixels from all layers. For tiled images, a data record holds one tile of pixels from all layers. Must be an integer greater than or equal to zero. Optional; defaults to zero. LAYER_SKIP_BYTES BSQ format only: the number of bytes to skip between image layers. Must be an integer greater than or equal to zero. Optional; defaults to zero. TILE_WIDTH Tiled format only: the number of pixels in the horizontal (x) direction per tile. Must be an integer greater than or equal to zero. and less than or equal to the image width. Optional; defaults to the minimum of 128 and the image width. TILE_HEIGHT Tiled format only: the number of pixels in the vertical (y) direction per tile. Must be an integer greater than or equal to zero. and less than or equal to the image width. Optional; defaults to the minimum of 128 and the image height. END_RAW_FILE Indicates the end of the raw file information. Useful if the raw file information is embedded within a larger file (perhaps the image file itself), it signals the DLL to stop scanning for further keywords. No associated values. Optional; if not present the DLL will scan to the end of the file. Examples Example 1: a 1201 x 1201-pixel DEM (Digital Elevation Model) file containing only pixel data, stored in the file "atlanta-e.dem" in the same directory as the raw file. The byte order is Motorola. IMAGINE_RAW_FILE WIDTH 1201 HEIGHT 1201 DATA_TYPE U16 PIXEL_FILES atlanta-e.dem BYTE_ORDER MSB Example 2: a 3-band image in BSQ format. All the data is in the file "/usr/people/Igscene.rgb". The file is 1000 pixels wide and 1500 pixels high. There is a 622-byte header at the start of the file. Each band contains a 2000 byte header and an 1000 byte trailer. IMAGINE_RAW_FILE WIDTH 1000 HEIGHT 1500 NUM_LAYERS 3 FORMAT BSQ PIXEL_FILES /usr/people/Igscene.rgb DATA_OFFSET 2622 LAYER_SKIP_BYTES 3000 Example 3: a 4-band image in BSQ format. Each layer is in a separate file, named "bandl.dat", "band2.dat", "band3.dat", and "band4.dat". The image is 6000 bytes wide and4000 bytes high. Each line of data contains 128 bytes of non-image data at the beginning and 32 bytes of non-image data at the end. IMAGINE_RAW_FILE NUM_LAYERS 4 WIDTH 6000 HEIGHT 4000 FORMAT BSQ PIXEL_FILES bandl.dat band2.dat band3.dat band4.dat DATA_OFFSET 128 RECORD_BYTE_SKIP 160 Example 4: A thematic image, 1024 by 1024 pixels, tiled with tile size 64 by 64 pixels. The image data is in the file "landcover.001": IMAGINE_RAW_FILE WIDTH 1024 HEIGHT 1024 FORMAT TILED TILE WIDTH 64 TILE HEIGHT 64 LAYER_TYPE THEMATIC PIXEL_FILES landcover.001

By: Okey	Date: 13/06/2003 21:00:00		Type : Comment
Nearly all popular File formats can be found at <A HREF="http://www.wotsit.org">http://www.wotsit.org</a>

By: lgdt	Date: 13/06/2003 21:20:00		Type : Comment
a RAW image doesn't have any file format, that's why it is RAW. It can be whatever you want: RGB, GS, CMYK it is like the bitmap part of a BMP file

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