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<p>Functions used to compute Reed-Solomon parity and check of byte arrays.
<a href="#details">More...</a></p>
<p><a href="rs_8h_source.html">Go to the source code of this file.</a></p>
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Macros</h2></td></tr>
<tr class="memitem:afdc383f8992f4a960bb22998f57b6d37"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#afdc383f8992f4a960bb22998f57b6d37">MM</a>   8 /* RS code over GF(2**MM) - change to suit */</td></tr>
<tr class="memdesc:afdc383f8992f4a960bb22998f57b6d37"><td class="mdescLeft"> </td><td class="mdescRight">Global definitions for Reed-Solomon encoder/decoder Phil Karn KA9Q, September 1996. <a href="#afdc383f8992f4a960bb22998f57b6d37">More...</a><br/></td></tr>
<tr class="separator:afdc383f8992f4a960bb22998f57b6d37"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a170755e30c36be4904106b7bb279b1ec"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#a170755e30c36be4904106b7bb279b1ec">NN</a>   ((1 << <a class="el" href="rs_8h.html#afdc383f8992f4a960bb22998f57b6d37">MM</a>) - 1)</td></tr>
<tr class="separator:a170755e30c36be4904106b7bb279b1ec"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ac6afabdc09a49a433ee19d8a9486056d"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#ac6afabdc09a49a433ee19d8a9486056d">min</a>(a, b)   (((a) < (b)) ? (a) : (b))</td></tr>
<tr class="memdesc:ac6afabdc09a49a433ee19d8a9486056d"><td class="mdescLeft"> </td><td class="mdescRight">Computes the minimum between two integers. <a href="#ac6afabdc09a49a433ee19d8a9486056d">More...</a><br/></td></tr>
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Typedefs</h2></td></tr>
<tr class="memitem:a9a32f7398bb29c52b13b76b584370222"><td class="memItemLeft" align="right" valign="top">typedef unsigned char </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#a9a32f7398bb29c52b13b76b584370222">dtype</a></td></tr>
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Functions</h2></td></tr>
<tr class="memitem:aa0ee9fc5ac4f8fee725e9cd9573ff71b"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#aa0ee9fc5ac4f8fee725e9cd9573ff71b">init_rs</a> (int)</td></tr>
<tr class="memdesc:aa0ee9fc5ac4f8fee725e9cd9573ff71b"><td class="mdescLeft"> </td><td class="mdescRight">Initialization function. <a href="#aa0ee9fc5ac4f8fee725e9cd9573ff71b">More...</a><br/></td></tr>
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<tr class="memitem:afa77e47615ab8c02fab3ca37e85a24dd"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#afa77e47615ab8c02fab3ca37e85a24dd">generate_gf</a> (void)</td></tr>
<tr class="memdesc:afa77e47615ab8c02fab3ca37e85a24dd"><td class="mdescLeft"> </td><td class="mdescRight">These two functions <em>must</em> be called in this order (e.g., by <a class="el" href="rs_8c.html#a3dad158bbf8c0e6402be80de973679a5" title="Initialization function. ">init_rs()</a>) before any encoding/decoding. <a href="#afa77e47615ab8c02fab3ca37e85a24dd">More...</a><br/></td></tr>
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<tr class="memitem:ac5ccf5e6e56bc414324daa9359571dd2"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#ac5ccf5e6e56bc414324daa9359571dd2">gen_poly</a> (void)</td></tr>
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<tr class="memitem:a6f81e64d6a0adf67aa3c7e1d28e3ddf1"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#a6f81e64d6a0adf67aa3c7e1d28e3ddf1">encode_rs</a> (<a class="el" href="rs_8h.html#a9a32f7398bb29c52b13b76b584370222">dtype</a> data[], <a class="el" href="rs_8h.html#a9a32f7398bb29c52b13b76b584370222">dtype</a> bb[])</td></tr>
<tr class="memdesc:a6f81e64d6a0adf67aa3c7e1d28e3ddf1"><td class="mdescLeft"> </td><td class="mdescRight">Reed-Solomon encoding data[] is the input block, parity symbols are placed in bb[] bb[] may lie past the end of the data, e.g., for (255,223): encode_rs(&data[0],&data[223]);. <a href="#a6f81e64d6a0adf67aa3c7e1d28e3ddf1">More...</a><br/></td></tr>
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<tr class="memitem:a033e2ded0c2c4975c5aee0dc09eadab6"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="rs_8h.html#a033e2ded0c2c4975c5aee0dc09eadab6">eras_dec_rs</a> (<a class="el" href="rs_8h.html#a9a32f7398bb29c52b13b76b584370222">dtype</a> data[], int eras_pos[], int no_eras)</td></tr>
<tr class="memdesc:a033e2ded0c2c4975c5aee0dc09eadab6"><td class="mdescLeft"> </td><td class="mdescRight">Reed-Solomon erasures-and-errors decoding The received block goes into data[], and a list of zero-origin erasure positions, if any, goes in eras_pos[] with a count in no_eras. <a href="#a033e2ded0c2c4975c5aee0dc09eadab6">More...</a><br/></td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p>Functions used to compute Reed-Solomon parity and check of byte arrays. </p>
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<td class="memname">#define min</td>
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<td></td><td>   (((a) < (b)) ? (a) : (b))</td>
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<p>Computes the minimum between two integers. </p>
<dl class="params"><dt>Parameters</dt><dd>
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<tr><td class="paramname">a</td><td>first integer to compare </td></tr>
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<dl class="section return"><dt>Returns</dt><dd>returns the minimum integer between a and b </dd></dl>
<p>Referenced by <a class="el" href="rs_8c.html#af1dc726419d303ffdcda6939bda11aae">eras_dec_rs()</a>, <a class="el" href="group___i_n_t.html#gab900976eb2a33a61c596189145fad7fc">int_clamp()</a>, <a class="el" href="group___j_p_w_l.html#ga241c44d08df58284bdc90125901ecfce">jpwl_epbs_add()</a>, <a class="el" href="group___t_c_d.html#ga95e1326c7801627873a59e065d541355">tcd_decode_tile()</a>, and <a class="el" href="group___t_c_d.html#ga7f0c1a599dee1eddda33b6ad08034709">tcd_rateallocate()</a>.</p>
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<td class="memname">#define MM   8 /* RS code over GF(2**MM) - change to suit */</td>
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<p>Global definitions for Reed-Solomon encoder/decoder Phil Karn KA9Q, September 1996. </p>
<p>The parameters MM and KK specify the Reed-Solomon code parameters.</p>
<p>Set MM to be the size of each code symbol in bits. The Reed-Solomon block size will then be NN = 2**M - 1 symbols. Supported values are defined in <a class="el" href="rs_8c.html" title="Functions used to compute the Reed-Solomon parity and check of byte arrays. ">rs.c</a>.</p>
<p>Set KK to be the number of data symbols in each block, which must be less than the block size. The code will then be able to correct up to NN-KK erasures or (NN-KK)/2 errors, or combinations thereof with each error counting as two erasures. </p>
<p>Referenced by <a class="el" href="rs_8h.html#afa77e47615ab8c02fab3ca37e85a24dd">generate_gf()</a>, and <a class="el" href="rs_8c.html#acf591e4e0cfd0b1cde804c679349947f">modnn()</a>.</p>
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<td class="memname">#define NN   ((1 << <a class="el" href="rs_8h.html#afdc383f8992f4a960bb22998f57b6d37">MM</a>) - 1)</td>
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<p>Referenced by <a class="el" href="rs_8c.html#a01e2c45240483af10538eb2d7ed56f81">encode_rs()</a>, <a class="el" href="rs_8c.html#af1dc726419d303ffdcda6939bda11aae">eras_dec_rs()</a>, <a class="el" href="rs_8h.html#ac5ccf5e6e56bc414324daa9359571dd2">gen_poly()</a>, <a class="el" href="rs_8h.html#afa77e47615ab8c02fab3ca37e85a24dd">generate_gf()</a>, <a class="el" href="rs_8h.html#aa0ee9fc5ac4f8fee725e9cd9573ff71b">init_rs()</a>, <a class="el" href="group___j_p_w_l.html#gac9eeaa750b40bcdf4fd1f01059a535cc">jpwl_epb_correct()</a>, <a class="el" href="group___j_p_w_l.html#ga65f414948b05e0bfad08023063dbdf96">jpwl_epb_fill()</a>, and <a class="el" href="rs_8c.html#acf591e4e0cfd0b1cde804c679349947f">modnn()</a>.</p>
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<h2 class="groupheader">Typedef Documentation</h2>
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<td class="memname">typedef unsigned char <a class="el" href="rs_8h.html#a9a32f7398bb29c52b13b76b584370222">dtype</a></td>
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<h2 class="groupheader">Function Documentation</h2>
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<td class="memname">int encode_rs </td>
<td>(</td>
<td class="paramtype"><a class="el" href="rs_8h.html#a9a32f7398bb29c52b13b76b584370222">dtype</a> </td>
<td class="paramname"><em>data</em>[], </td>
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<p>Reed-Solomon encoding data[] is the input block, parity symbols are placed in bb[] bb[] may lie past the end of the data, e.g., for (255,223): encode_rs(&data[0],&data[223]);. </p>
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<td class="memname">int eras_dec_rs </td>
<td>(</td>
<td class="paramtype"><a class="el" href="rs_8h.html#a9a32f7398bb29c52b13b76b584370222">dtype</a> </td>
<td class="paramname"><em>data</em>[], </td>
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<td class="paramtype">int </td>
<td class="paramname"><em>eras_pos</em>[], </td>
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<p>Reed-Solomon erasures-and-errors decoding The received block goes into data[], and a list of zero-origin erasure positions, if any, goes in eras_pos[] with a count in no_eras. </p>
<p>The decoder corrects the symbols in place, if possible and returns the number of corrected symbols. If the codeword is illegal or uncorrectible, the data array is unchanged and -1 is returned </p>
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<td class="memname">void gen_poly </td>
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<p>References <a class="el" href="rs_8c.html#aaa77e8ef556afba0da22dae38b0ea8ea">Alpha_to</a>, <a class="el" href="rs_8c.html#a8a03ef52aa4926d1d75cb647ac768622">B0</a>, <a class="el" href="rs_8c.html#af474e09bee18450627e4c7d40419e973">Gg</a>, <a class="el" href="rs_8c.html#aadc731ecca09ed2f114b3c30ce5c4982">Index_of</a>, <a class="el" href="rs_8c.html#a086193b71e7c24768de1dc748b817c8c">KK</a>, <a class="el" href="rs_8c.html#acf591e4e0cfd0b1cde804c679349947f">modnn()</a>, and <a class="el" href="rs_8h.html#a170755e30c36be4904106b7bb279b1ec">NN</a>.</p>
<p>Referenced by <a class="el" href="rs_8h.html#aa0ee9fc5ac4f8fee725e9cd9573ff71b">init_rs()</a>.</p>
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<td class="memname">void generate_gf </td>
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<p>These two functions <em>must</em> be called in this order (e.g., by <a class="el" href="rs_8c.html#a3dad158bbf8c0e6402be80de973679a5" title="Initialization function. ">init_rs()</a>) before any encoding/decoding. </p>
<p>References <a class="el" href="rs_8c.html#a0d158f1e3af2ab523eb8423db3e5bd6e">A0</a>, <a class="el" href="rs_8c.html#aaa77e8ef556afba0da22dae38b0ea8ea">Alpha_to</a>, <a class="el" href="rs_8c.html#aadc731ecca09ed2f114b3c30ce5c4982">Index_of</a>, <a class="el" href="rs_8h.html#afdc383f8992f4a960bb22998f57b6d37">MM</a>, <a class="el" href="rs_8h.html#a170755e30c36be4904106b7bb279b1ec">NN</a>, and <a class="el" href="rs_8c.html#ac4465651339912643627d98d70a2c131">Pp</a>.</p>
<p>Referenced by <a class="el" href="rs_8h.html#aa0ee9fc5ac4f8fee725e9cd9573ff71b">init_rs()</a>.</p>
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<td class="memname">void init_rs </td>
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<p>Initialization function. </p>
<p>References <a class="el" href="rs_8c.html#ac5ccf5e6e56bc414324daa9359571dd2">gen_poly()</a>, <a class="el" href="rs_8c.html#afa77e47615ab8c02fab3ca37e85a24dd">generate_gf()</a>, <a class="el" href="rs_8c.html#a086193b71e7c24768de1dc748b817c8c">KK</a>, and <a class="el" href="rs_8h.html#a170755e30c36be4904106b7bb279b1ec">NN</a>.</p>
<p>Referenced by <a class="el" href="group___j_p_w_l.html#gac9eeaa750b40bcdf4fd1f01059a535cc">jpwl_epb_correct()</a>, and <a class="el" href="group___j_p_w_l.html#ga65f414948b05e0bfad08023063dbdf96">jpwl_epb_fill()</a>.</p>
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