/*!
* pixWriteMemWebP()
*
* Input: &encdata (<return> webp encoded data of pixs)
* &encsize (<return> size of webp encoded data)
* pixs (any depth, cmapped OK)
* quality (0 - 100; default ~80)
* lossless (use 1 for lossless; 0 for lossy)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) Lossless and lossy encoding are entirely different in webp.
* @quality applies to lossy, and is ignored for lossless.
* (2) The input image is converted to RGB if necessary. If spp == 3,
* we set the alpha channel to fully opaque (255), and
* WebPEncodeRGBA() then removes the alpha chunk when encoding,
* setting the internal header field has_alpha to 0.
*/
l_int32
pixWriteMemWebP(l_uint8 **pencdata,
size_t *pencsize,
PIX *pixs,
l_int32 quality,
l_int32 lossless)
{
l_int32 w, h, d, wpl, stride;
l_uint32 *data;
PIX *pix1, *pix2;
PROCNAME("pixWriteMemWebP");
if (!pencdata)
return ERROR_INT("&encdata not defined", procName, 1);
*pencdata = NULL;
if (!pencsize)
return ERROR_INT("&encsize not defined", procName, 1);
*pencsize = 0;
if (!pixs)
return ERROR_INT("&pixs not defined", procName, 1);
if (lossless == 0 && (quality < 0 || quality > 100))
return ERROR_INT("quality not in [0 ... 100]", procName, 1);
if ((pix1 = pixRemoveColormap(pixs, REMOVE_CMAP_TO_FULL_COLOR)) == NULL)
return ERROR_INT("failure to remove color map", procName, 1);
/* Convert to rgb if not 32 bpp; pix2 must not be a clone of pixs. */
if (pixGetDepth(pix1) != 32)
pix2 = pixConvertTo32(pix1);
else
pix2 = pixCopy(NULL, pix1);
pixDestroy(&pix1);
pixGetDimensions(pix2, &w, &h, &d);
if (w <= 0 || h <= 0 || d != 32) {
pixDestroy(&pix2);
return ERROR_INT("pix2 not 32 bpp or of 0 size", procName, 1);
}
/* If spp == 3, need to set alpha layer to opaque (all 1s). */
if (pixGetSpp(pix2) == 3)
pixSetComponentArbitrary(pix2, L_ALPHA_CHANNEL, 255);
/* Webp encoder assumes big-endian byte order for RGBA components */
pixEndianByteSwap(pix2);
wpl = pixGetWpl(pix2);
data = pixGetData(pix2);
stride = wpl * 4;
if (lossless) {
*pencsize = WebPEncodeLosslessRGBA((uint8_t *)data, w, h,
stride, pencdata);
} else {
*pencsize = WebPEncodeRGBA((uint8_t *)data, w, h, stride,
quality, pencdata);
}
pixDestroy(&pix2);
if (*pencsize == 0) {
free(pencdata);
*pencdata = NULL;
return ERROR_INT("webp encoding failed", procName, 1);
}
return 0;
}
/*!
* \brief pixWriteMemWebP()
*
* \param[out] pencdata webp encoded data of pixs
* \param[out] pencsize size of webp encoded data
* \param[in] pixs any depth, cmapped OK
* \param[in] quality 0 - 100; default ~80
* \param[in] lossless use 1 for lossless; 0 for lossy
* \return 0 if OK, 1 on error
*
* <pre>
* Notes:
* (1) Lossless and lossy encoding are entirely different in webp.
* %quality applies to lossy, and is ignored for lossless.
* (2) The input image is converted to RGB if necessary. If spp == 3,
* we set the alpha channel to fully opaque (255), and
* WebPEncodeRGBA() then removes the alpha chunk when encoding,
* setting the internal header field has_alpha to 0.
* </pre>
*/
l_ok
pixWriteMemWebP(l_uint8 **pencdata,
size_t *pencsize,
PIX *pixs,
l_int32 quality,
l_int32 lossless)
{
l_int32 w, h, d, wpl, stride;
l_uint32 *data;
PIX *pix1, *pix2;
PROCNAME("pixWriteMemWebP");
if (!pencdata)
return ERROR_INT("&encdata not defined", procName, 1);
*pencdata = NULL;
if (!pencsize)
return ERROR_INT("&encsize not defined", procName, 1);
*pencsize = 0;
if (!pixs)
return ERROR_INT("&pixs not defined", procName, 1);
if (lossless == 0 && (quality < 0 || quality > 100))
return ERROR_INT("quality not in [0 ... 100]", procName, 1);
if ((pix1 = pixRemoveColormap(pixs, REMOVE_CMAP_TO_FULL_COLOR)) == NULL)
return ERROR_INT("failure to remove color map", procName, 1);
/* Convert to rgb if not 32 bpp; pix2 must not be a clone of pixs. */
if (pixGetDepth(pix1) != 32)
pix2 = pixConvertTo32(pix1);
else
pix2 = pixCopy(NULL, pix1);
pixDestroy(&pix1);
pixGetDimensions(pix2, &w, &h, &d);
if (w <= 0 || h <= 0 || d != 32) {
pixDestroy(&pix2);
return ERROR_INT("pix2 not 32 bpp or of 0 size", procName, 1);
}
/* If spp == 3, need to set alpha layer to opaque (all 1s). */
if (pixGetSpp(pix2) == 3)
pixSetComponentArbitrary(pix2, L_ALPHA_CHANNEL, 255);
/* The WebP API expects data in RGBA order. The pix stores
* in host-dependent order with R as the MSB and A as the LSB.
* On little-endian machines, the bytes in the word must
* be swapped; e.g., R goes from byte 0 (LSB) to byte 3 (MSB).
* No swapping is necessary for big-endians. */
pixEndianByteSwap(pix2);
wpl = pixGetWpl(pix2);
data = pixGetData(pix2);
stride = wpl * 4;
if (lossless) {
*pencsize = WebPEncodeLosslessRGBA((uint8_t *)data, w, h,
stride, pencdata);
} else {
*pencsize = WebPEncodeRGBA((uint8_t *)data, w, h, stride,
quality, pencdata);
}
pixDestroy(&pix2);
if (*pencsize == 0) {
free(*pencdata);
*pencdata = NULL;
return ERROR_INT("webp encoding failed", procName, 1);
}
return 0;
}
