NOAA has already started to cancel individual charts and will shut down all production and maintenance of traditional paper nautical charts and the associated raster chart products and services by January 2025.
Just as NOAA electronic navigational chart (NOAA ENC) cells do, all raster charts portray water depths,coastlines, dangers, aids to navigation, landmarks, bottom characteristics and other features, as well as regulatory, tide, and other information. All raster chart products are based on and have the same appearance as the "traditional" paper charts that Coast Survey has provided for U.S. waters since the early 19th century.
Raster Nng V1.0 Downloadl
The U. S. Government no longer prints paper copies of its raster nautical charts. However, NOAA provides digital images of its raster charts to NOAA certified chart agents, from whom the public may purchase NOAA paper nautical charts.
Certified chart agents ensure that the charts are printed at the proper scale and quality to meet U.S. Coast Guard (USCG) chart carriage requirements. In fact, only charts printed by a NOAA certified chart agent are accepted by the USCG as meeting chart carriage requirements for commercial vessels. No other raster chart format meets USCG carriage requirements.
Natural Earth is a public domain map dataset available at 1:10m, 1:50m, and 1:110 million scales. Featuring tightly integrated vector and raster data, with Natural Earth you can make a variety of visually pleasing, well-crafted maps with cartography or GIS software.
Mapping Toolbox supports a complete workflow for managing geographic data. You can import vector and raster data from a wide range of file formats and web map servers. The toolbox lets you process and customize data using trimming, interpolation, resampling, coordinate transformations, and other techniques. Data can be combined with base map layers from multiple sources in a single map display. You can export data in file formats such as shapefile, GeoTIFF, and KML.
Import vector and raster GIS and geospatial data into the MATLAB environment. Export and raster data to standard formats and share with Geographic Information Systems and other geospatial applications.
2NOTE: Subscription feature; when you purchase a new Garmin Navionics+ or Garmin Navionics Vision+ cartography product, a one-year subscription is included. The subscription includes access to daily chart updates and download of additional content such as raster cartography and premium features (high-resolution relief shading, high-resolution satellite imagery and sonar imagery) where available. Charts and features downloaded during the subscription period remain on the card, but no additional content can be downloaded after the subscription expires.
Your raster size is 0x0 since your extent is only about 0.08 degrees latitude (the difference between North and South) yet you are asking for a resolution of 2.1174 degrees latitude. Ditto for East-West.
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems.[2][3] Based on the PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991.[4]
Raster images in PDF (called Image XObjects) are represented by dictionaries with an associated stream. The dictionary describes the properties of the image, and the stream contains the image data. (Less commonly, small raster images may be embedded directly in a page description as an inline image.) Images are typically filtered for compression purposes. Image filters supported in PDF include the following general-purpose filters:
Raster image processors (RIPs) are used to convert PDF files into a raster format suitable for imaging onto paper and other media in printers, digital production presses and prepress in a process known as rasterization. RIPs capable of processing PDF directly include the Adobe PDF Print Engine[72] from Adobe Systems and Jaws[73] and the Harlequin RIP from Global Graphics.
In 1993, the Jaws raster image processor from Global Graphics became the first shipping prepress RIP that interpreted PDF natively without conversion to another format. The company released an upgrade to their Harlequin RIP with the same capability in 1997.[74]
As usual, CLASS definitions are evaluated in order from first tolast, and the first to match is used. If a CLASS has a NAMEattribute it may appear in a LEGEND. Only the COLOR, EXPRESSIONand NAME parameters within a CLASS definition are utilized forraster classifications. The other styling or control information isignored.
Raster classifications always take place on only one raster band. It defaultsto the first band in the referenced file, but this can be altered with theBANDS PROCESSING directive. In particular this means that including even asingle CLASS declaration in a raster layer will result in the raster layerbeing rendered using the one band classification rules instead of other rulesthat might have applied (such as 3 band RGB rendering).
As of MapServer 4.4 support has been added for classifying non-8bit rasterinputs. That is input rasters with values outside the range 0-255. Mostly thisworks transparently but there are a few caveats and options to provideexplicit control.
Classifying raster data in MapServer is accomplished by pre-classifying allexpected input values and using that table of classification results to lookupeach pixel as it is rendered. This is done because evaluating a pixel valueagainst a series of CLASS definitions is relatively expensive to do for thehundreds of thousands of pixels in a typical rendered image.
The following example shows a simple example. No DATA statement is requiredbecause MapServer will fetch the filename of the raster files from theLocation attribute column in the hp2.dbf file for records associated withpolygons in hp2.shp that intersect the current display region. The polygons inhp2.shp should be rectangles representing the footprint of the correspondingfile. Note that the files do not have to be all the same size, the formats canvary and they can even overlap (later files will be drawn over earlier ones).
While there are many ways to produce TILEINDEX shapefiles for use with thiscommand, one option is the gdaltindex program, part of the GDAL utilitysuite. The gdaltindex program will automatically generate a tile indexshapefile from a list of GDAL supported raster files passed on the commandline.
Simple rectangular polygons must be generated in the samecoordinate system as the raster layer. If the files in the tileindex arenot in the same projection as the raster layer, or are in heterogeneousprojections, the TILESRS keyword must be specified in the LAYER definition.See Tileindexes with tiles in different projections
Raster warping kicks in if the projection appears to be different for a rasterlayer than for the map being generated. Warped raster layers are significantlymore expensive to render than normal raster layers with rendering time beingperhaps 2-4 times long than a normal layer. The projection and datum shiftingtransformation is computed only at selected points, and generally linearlyinterpolated along the scanlines (as long as the error appears to be less than0.333 pixels.
Traditionally MapServer has been used to produce 8 bit pseudo-colored mapdisplays generated from 8bit greyscale or pseudocolored raster data. However,if the raster file to be rendered is actually 24bit (a red, green and blueband) then additional considerations come into play. Rendering of24bit imagery is supported via the GDAL renderer.
If the output is still 8bit pseudo-colored (the IMAGEMODE is PC256 in theassociated OUTPUTFORMAT declaration) then the full 24bit RGB colors for inputpixels will be converted to a color in the colormap of the output image. Bydefault a color cube is used. That is a fixed set of 175 colors providing 5levels of red, 7 levels of green and 5 levels of blue is used, plus anadditional 32 greyscale color entries. Colors in the input raster are mappedto the closest color in this color cube on the fly. This substantial degradescolor quality, especially for smoothly changing images. It also fills up thecolors table, limited to 256 colors, quite quickly.
As of MapServer 4.0, the PROCESSING parameter was added to the LAYER ofthe Mapfile. It is primarily used to pass specialized raster processingoptions to the GDAL based raster renderer. The following processing optionsare supported in MapServer 4.0 and newer.
This directive allows a specific band or bands to be selected from araster file. If one band is selected, it is treated as greyscale. If 3 areselected, they are treated as red, green and blue. If 4 are selected theyare treated as red, green, blue and alpha (opacity).
Starting with MapServer 7.2, the range of input values can go up to 65535.The last point of the curve must be explicitly listed, e.g. for a 12-bitraster, 4095:255. This extended LUT syntax is only properly supported ifno SCALE directive is specified, since the purpose of extended LUT is mainly toavoid pre-scaling.
This option can be used to control the resampling kernel used samplingraster images. The default (and fastest) is NEAREST. AVERAGE will performcompute the average pixel value of all pixels in the region of the diskfile being mapped to the output pixel (or possibly just a sampling ofthem). BILINEAR will compute a linear interpolation of the four pixelsaround the target location. This topic is discussed in more detail inMS RFC 4: MapServer Raster Resampling.
Resampling options other than NEAREST result in use of the generalizedwarper and can dramatically slow down raster processing. Generally AVERAGEcan be desirable for reducing noise in dramatically downsampled data, andcan give something approximating antialiasing for black and whitelinework. BILINEAR can be helpful when oversampling data to give a smoothappearance. 2ff7e9595c
Kommentare