![]() JPEG-Lossy compression uses the public JPEG compression algorithm.LERC-Lossless or lossy compression divides the raster into a number of pixel.LZ77-Lossless compression preserves all raster cell values.A maximum error of 0.000000 means that lossless compression will be used.Ī = "compression_type " Max error-When LERC compression is chosen, the maximum error also must be specified, which is expressed in the same units as the raster resolution.The valid compression quality value ranges are from 1 to 100, with 75 being the default. Compression quality (1-100)-When JPEG, JPEG_YCbCr, or JPEG2000 compression is chosen, the compression quality also must be specified.The valid compression quality value ranges are from 0 to 100, with 75 being the default. If you choose JPEG_YCbCr, you can also specify the compression quality. JPEG_YCbCr-Lossless compression using the luma (Y) and chroma (Cb and Cr) color space components.CCITT_1D-Lossless compression for 1-bit data.CCITT_G4-Lossless compression for 1-bit data.CCITT_G3-Lossless compression for 1-bit data.LZW-Lossless compression that preserves all raster cell values.PackBits- PackBits compression for TIFF files.This compression can be used for JPEG 2000 files and geodatabases. If you choose JPEG2000, you can also specify the compression quality. JPEG2000-Uses wavelet technology so rasters appear lossless.This compression can be used for JPEG files, TIFF files, and geodatabases. If you choose JPEG, you can also specify the compression quality. JPEG-Lossy compression that uses the public JPEG compression algorithm.LERC-Lossless or lossy compression that divides the raster into a number of pixelīlocks, in which each pixel can be quantized and bit.LZ77-Lossless compression that preserves all raster cell values.Compression-Choose which compression method to use when storing your data.This setting is used for tools that create raster datasets in ArcGIS.The following table summarizes the valid compression types for each pixel depth: Valid compressions for each pixel depthĪs pixel depth increases, so does the efficiency of the compression algorithm.The maximum error is a tolerance value that is applicable Stuffed, based on a number of block statistics, including In which each pixel can be quantized and bit Method that can divide raster into a number of pixel LERC compression is an image compression.The default compression type is LZ77 and it works for all types of raster data.If you don't explicitly set a value, the default will be used. Valid value ranges of compression quality are from 1 to 100. The values of the pixels of an image compressed with a higher compression quality will be closer to those of the original image. If JPEG, JPEG_YCbCr, or JPEG2000 is selected, you can also set the compression quality to control how much loss the image will be subjected to by the compression algorithm.JPEG compression only works for unsigned 8-bit raster data and unsigned 12-bit data (stored as 16-bit data).File and enterprise geodatabases only support LZ77, JPEG, JPEG2000,.When storing data in a geodatabase, compression occurs before storage in the geodatabase.Lossy compression normally results in higher compression ratios when compared to lossless compression. The lower the compression quality, the higher the compression ratio. The more homogeneous the data, the higher the compression ratio. The amount of compression will depend on the data and compression quality. You should choose lossless or no compression if the pixel values of the raster dataset will be used for analysis or deriving other data products. Lossless compression means that the values of cells in the raster dataset are not changed or lost. ![]() When storing data in the geodatabase, the blocks of data are compressed before they are stored.ĭata compression can be lossy (JPEG and JPEG 2000) or lossless (LZ77, PackBits, CCITT). The primary benefits of compressing data are that compressed data requires less storage space, and data display times will be quicker because there is less information to transmit.ĪrcGIS can store compressed data in the following formats: IMG, JPEG, JPEG 2000, TIFF, Esri Grid, or in a geodatabase. Tools that honor the Compression environment will set the compression type when storing output raster datasets.
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