sws: handle non native rgb<->rgb convertions

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libswscale/swscale_unscaled.c

@@ -542,10 +542,6 @@ static rgbConvFn findRgbConvFn(SwsContext *c)
     (((bpp + 7) >> 3) == 2 && \
      (!(av_pix_fmt_descriptors[fmt].flags & PIX_FMT_BE) != !HAVE_BIGENDIAN))
 
-    /* if this is non-native rgb444/555/565, don't handle it here. */
-    if (IS_NOT_NE(srcId, srcFormat) || IS_NOT_NE(dstId, dstFormat))
-        return NULL;
-
 #define CONV_IS(src, dst) (srcFormat == PIX_FMT_##src && dstFormat == PIX_FMT_##dst)
 
     if (isRGBA32(srcFormat) && isRGBA32(dstFormat)) {
@@ -632,6 +628,9 @@ static int rgbToRgbWrapper(SwsContext *c, const uint8_t *src[], int srcStride[],
     } else {
         const uint8_t *srcPtr = src[0];
               uint8_t *dstPtr = dst[0];
+        int src_bswap = IS_NOT_NE(c->srcFormatBpp, srcFormat);
+        int dst_bswap = IS_NOT_NE(c->dstFormatBpp, dstFormat);
+
         if ((srcFormat == PIX_FMT_RGB32_1 || srcFormat == PIX_FMT_BGR32_1) &&
             !isRGBA32(dstFormat))
             srcPtr += ALT32_CORR;
@@ -641,15 +640,23 @@ static int rgbToRgbWrapper(SwsContext *c, const uint8_t *src[], int srcStride[],
             dstPtr += ALT32_CORR;
 
         if (dstStride[0] * srcBpp == srcStride[0] * dstBpp && srcStride[0] > 0 &&
-            !(srcStride[0] % srcBpp))
+            !(srcStride[0] % srcBpp) && !dst_bswap && !src_bswap)
             conv(srcPtr, dstPtr + dstStride[0] * srcSliceY,
                  srcSliceH * srcStride[0]);
         else {
-            int i;
+            int i, j;
             dstPtr += dstStride[0] * srcSliceY;
 
             for (i = 0; i < srcSliceH; i++) {
-                conv(srcPtr, dstPtr, c->srcW * srcBpp);
+                if(src_bswap) {
+                    for(j=0; j<c->srcW; j++)
+                        ((uint16_t*)c->formatConvBuffer)[j] = av_bswap16(((uint16_t*)srcPtr)[j]);
+                    conv(c->formatConvBuffer, dstPtr, c->srcW * srcBpp);
+                }else
+                    conv(srcPtr, dstPtr, c->srcW * srcBpp);
+                if(dst_bswap)
+                    for(j=0; j<c->srcW; j++)
+                        ((uint16_t*)dstPtr)[j] = av_bswap16(((uint16_t*)dstPtr)[j]);
                 srcPtr += srcStride[0];
                 dstPtr += dstStride[0];
             }

libswscale/utils.c

@@ -996,6 +996,8 @@ int sws_init_context(SwsContext *c, SwsFilter *srcFilter, SwsFilter *dstFilter)
     c->chrDstW = -((-dstW) >> c->chrDstHSubSample);
     c->chrDstH = -((-dstH) >> c->chrDstVSubSample);
 
+    FF_ALLOC_OR_GOTO(c, c->formatConvBuffer, FFALIGN(srcW*2+78, 16) * 2, fail);
+
     /* unscaled special cases */
     if (unscaled && !usesHFilter && !usesVFilter &&
         (c->srcRange == c->dstRange || isAnyRGB(dstFormat))) {
@@ -1020,7 +1022,6 @@ int sws_init_context(SwsContext *c, SwsFilter *srcFilter, SwsFilter *dstFilter)
         c->srcBpc = 16;
     if (c->dstBpc == 16)
         dst_stride <<= 1;
-    FF_ALLOC_OR_GOTO(c, c->formatConvBuffer, FFALIGN(srcW*2+78, 16) * 2, fail);
     if (HAVE_MMX2 && cpu_flags & AV_CPU_FLAG_MMX2 &&
         c->srcBpc == 8 && c->dstBpc <= 14) {
         c->canMMX2BeUsed = (dstW >= srcW && (dstW & 31) == 0 &&