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    <p>Assumeing the following API to get the image:</p> <pre><code>int ImageGet( char * pBuffer, size_t * pSize); /* returns 0 on success or any other value if no image is available or on error */ </code></pre> <p>you could do the following:</p> <pre><code>#include &lt;stdlib.h&gt; #include &lt;string.h&gt; ... #define IMAGESIZE_MAX (1024*1024) char * pBuffer = NULL; char * pBufferCurrent = pBuffer; int iResult = 0; size_t size = IMAGESIZE_MAX; size_t sizeTotal = 0; do { char * pBufferCurrent = realloc ( pBuffer, sizeTotal + sizeof(size) + size); if (!pBufferCurrent) { break; } pBuffer = pBufferCurrent; pBufferCurrent += sizeTotal; if ((iResult = ImageGet ( pBufferCurrent + sizeof(size), &amp;size)) { break; } memcpy ( pBufferCurrent, &amp;size, sizeof(size)); sizeTotal += (sizeof(size) + size); } while (1); ... </code></pre> <p>This stores your data sequentially:</p> <pre><code>[ size 1 ][ image data 1 ][ size 2 ][ image data 2 ]... &lt;-sizeof(size_t)-&gt;&lt;- size 1 -&gt;&lt;-sizeof(size_t)-&gt;&lt;- size 2 -&gt; </code></pre> <p>in the buffer pointed to by <code>pBuffer</code>.</p> <hr> <p>To retrieve a reference to the data describing image N from the buffer <code>pBuffer</code> you could use the following method:</p> <pre><code>const char * BufferImageGetByIndex( const char * pBuffer, unsigned indexImage) { for (unsigned indexImageCnt = 0; indexImageCnt &lt; indexImage; ++ indexImageCnt) { pBuffer += sizeof(size_t) + *((size_t *) pBuffer); } return pBuffer; } </code></pre> <p>Then to actually get an image you could do like so:</p> <pre><code>... /* Get a reference to the data decribing **fourth** image in the buffer filled by the example above. */ const char * pBufferImage4 = *BufferImageGetByIndex(pBuffer, 3); /* Get the size ... */ size_t sizeImage4 = *((size_t *) pBufferImage4); /* ... and a reference to the image data. */ const char * pImage4 = pBufferImage4 + sizeof(size_t); ... </code></pre>
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    1. POA Memory buffer for multiple images
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    1. POA Memory buffer for multiple images
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    1. COOne minor nitpick: Instead of defining IMAGESIZE_MAX to be a multiplication that needs to be evaluated at each check against the max, just make it the answer (1084576). Yeah it will be compiled as a simple 10-bit left shift, but there's no need to waste instructions willy-nilly.
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    2. COI thought I might leave this as an exercise to the OP ... ;-) - no, to be honest I simply couldn't remember the result and I was too lazy start a calculator and even more to lazy too use my brain ... and I felt 1024 bytes might be unrealistic small for an image buffer these days @pg1989
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    3. CONo worries, I know the feeling all too well.
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