1Pamvalidate User Manual(0) Pamvalidate User Manual(0)
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6 pamvalidate - validate Netpbm image format
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10 pamvalidate
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15 This program is part of Netpbm(1).
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17 pamvalidate copies a Netpbm image from Standard Input to Standard Out‐
18 put, except that if there are certain violations of the image format in
19 the input, pamvalidate fails without producing any output.
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21 This is most useful in a pipeline, before a stage you don't want to
22 start working on Netpbm input until it knows it can get all the way
23 through it. For example, assume you are converting PPM images to PNG
24 and you don't want to produce a partial PNG file under any circum‐
25 stance. If you just use pnmtopng, and the PPM input is truncated half‐
26 way through the raster, pnmtopng fails, but also produces about half of
27 a PNG file. To prevent that, pass your PPM input through pamvalidate
28 on its way to pnmtopng. Then, pamvalidate will fail, and consequently
29 the pipeline will fail, before pnmtopng has seen any input and there‐
30 fore before pnmtopng has produced any output.
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32 These are the kinds of format violations pamvalidate detects:
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36 · A purported sample value exceeds the declared maxval.
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38 · The stream ends prematurely.
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41 This program works on multi-image streams, producing a corresponding
42 output stream.
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44 See pamfix for a way to salvage an invalid Netpbm image stream.
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49 There are no command line options defined specifically for pamvalidate,
50 but it recognizes the options common to all programs based on libnetpbm
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52 Common Options ⟨index.html#commonoptions⟩ .)
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56 pam(1) pnm(1) pamfix(1)
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61 pamvalidate was new in Netpbm 10.66 (March 2014).
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64 This manual page was generated by the Netpbm tool 'makeman' from HTML
65 source. The master documentation is at
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67 http://netpbm.sourceforge.net/doc/pamvalidate.html
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69netpbm documentation 22 March 2014 Pamvalidate User Manual(0)