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@@ -3174,7 +3174,7 @@ If you choose option 1, then <code>*jpegSize</code> should be set to the size of
<tr><td class="paramname">dstBufs</td><td>pointer to an array of n byte buffers. <code>dstBufs[i]</code> will receive a JPEG image that has been transformed using the parameters in <code>transforms[i]</code>. TurboJPEG has the ability to reallocate the JPEG destination buffer to accommodate the size of the transformed JPEG image. Thus, you can choose to:<ol type="1">
<li>pre-allocate the JPEG destination buffer with an arbitrary size using <a class="el" href="group___turbo_j_p_e_g.html#ga1a2c96d8b47530b6e6050ba6f10b7c57" title="Allocate a byte buffer for use with TurboJPEG.">tj3Alloc()</a> and let TurboJPEG grow the buffer as needed,</li>
<li>set <code>dstBufs[i]</code> to NULL to tell TurboJPEG to allocate the buffer for you, or</li>
<li>pre-allocate the buffer to a "worst case" size determined by calling <a class="el" href="group___turbo_j_p_e_g.html#gac6285e58e35a35d871d7162ec5a929c4" title="The maximum size of the buffer (in bytes) required to hold a JPEG image with the given parameters.">tj3JPEGBufSize()</a> with the transformed or cropped width and height and the level of subsampling used in the source image. Under normal circumstances, this should ensure that the buffer never has to be re-allocated. (Setting <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82ae64ffb358bc7b194fd48e0f27750b29b" title="JPEG destination buffer (re)allocation [compression, lossless transformation].">TJPARAM_NOREALLOC</a> guarantees that it won't be.) Note, however, that there are some rare cases (such as transforming images with a large amount of embedded Exif or ICC profile data) in which the transformed JPEG image will be larger than the worst-case size, and <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82ae64ffb358bc7b194fd48e0f27750b29b" title="JPEG destination buffer (re)allocation [compression, lossless transformation].">TJPARAM_NOREALLOC</a> cannot be used in those cases.</li>
<li>pre-allocate the buffer to a "worst case" size determined by calling <a class="el" href="group___turbo_j_p_e_g.html#gac6285e58e35a35d871d7162ec5a929c4" title="The maximum size of the buffer (in bytes) required to hold a JPEG image with the given parameters.">tj3JPEGBufSize()</a> with the transformed or cropped width and height and the level of subsampling used in the destination image (taking into account grayscale conversion and transposition of the width and height.) Under normal circumstances, this should ensure that the buffer never has to be re-allocated. (Setting <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82ae64ffb358bc7b194fd48e0f27750b29b" title="JPEG destination buffer (re)allocation [compression, lossless transformation].">TJPARAM_NOREALLOC</a> guarantees that it won't be.) Note, however, that there are some rare cases (such as transforming images with a large amount of embedded Exif or ICC profile data) in which the transformed JPEG image will be larger than the worst-case size, and <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82ae64ffb358bc7b194fd48e0f27750b29b" title="JPEG destination buffer (re)allocation [compression, lossless transformation].">TJPARAM_NOREALLOC</a> cannot be used in those cases unless the embedded data is discarded using <a class="el" href="group___turbo_j_p_e_g.html#ga153b468cfb905d0de61706c838986fe8" title="Do not copy any extra markers (including Exif and ICC profile data) from the source image to the dest...">TJXOPT_COPYNONE</a>.</li>
</ol>
If you choose option 1, then <code>dstSizes[i]</code> should be set to the size of your pre-allocated buffer. In any case, unless you have set <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82ae64ffb358bc7b194fd48e0f27750b29b" title="JPEG destination buffer (re)allocation [compression, lossless transformation].">TJPARAM_NOREALLOC</a>, you should always check <code>dstBufs[i]</code> upon return from this function, as it may have changed.</td></tr>
<tr><td class="paramname">dstSizes</td><td>pointer to an array of n size_t variables that will receive the actual sizes (in bytes) of each transformed JPEG image. If <code>dstBufs[i]</code> points to a pre-allocated buffer, then <code>dstSizes[i]</code> should be set to the size of the buffer. Upon return, <code>dstSizes[i]</code> will contain the size of the transformed JPEG image (in bytes.)</td></tr>