Unscaled Planar RGB -> RGB support in swscale.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

libswscale/swscale_internal.h

@@ -627,6 +627,14 @@ const char *sws_format_name(enum PixelFormat format);
     (av_pix_fmt_descriptors[x].nb_components >= 2          &&  \
      (av_pix_fmt_descriptors[x].flags & PIX_FMT_PLANAR))
 
+#define isPackedRGB(x)                                         \
+    ((av_pix_fmt_descriptors[x].flags                        & \
+     (PIX_FMT_PLANAR | PIX_FMT_RGB)) == PIX_FMT_RGB)
+
+#define isPlanarRGB(x)                                         \
+    ((av_pix_fmt_descriptors[x].flags                        & \
+     (PIX_FMT_PLANAR | PIX_FMT_RGB)) == (PIX_FMT_PLANAR | PIX_FMT_RGB))
+
 #define usePal(x) ((av_pix_fmt_descriptors[x].flags & PIX_FMT_PAL) ||       \
                    (av_pix_fmt_descriptors[x].flags & PIX_FMT_PSEUDOPAL) || \
                    (x) == PIX_FMT_Y400A)

libswscale/swscale_unscaled.c

@@ -344,6 +344,108 @@ static int palToRgbWrapper(SwsContext *c, const uint8_t *src[], int srcStride[],
     return srcSliceH;
 }
 
+static void gbr24ptopacked24(const uint8_t *src[], int srcStride[],
+                             uint8_t *dst, int dstStride, int srcSliceH,
+                             int width)
+{
+    int x, h, i;
+    for (h = 0; h < srcSliceH; h++) {
+        uint8_t *dest = dst + dstStride * h;
+        for (x = 0; x < width; x++) {
+            *dest++ = src[0][x];
+            *dest++ = src[1][x];
+            *dest++ = src[2][x];
+        }
+
+        for (i = 0; i < 3; i++)
+            src[i] += srcStride[i];
+    }
+}
+
+static void gbr24ptopacked32(const uint8_t *src[], int srcStride[],
+                             uint8_t *dst, int dstStride, int srcSliceH,
+                             int alpha_first, int width)
+{
+    int x, h, i;
+    for (h = 0; h < srcSliceH; h++) {
+        uint8_t *dest = dst + dstStride * h;
+
+        if (alpha_first) {
+            for (x = 0; x < width; x++) {
+                *dest++ = 0xff;
+                *dest++ = src[0][x];
+                *dest++ = src[1][x];
+                *dest++ = src[2][x];
+            }
+        } else {
+            for (x = 0; x < width; x++) {
+                *dest++ = src[0][x];
+                *dest++ = src[1][x];
+                *dest++ = src[2][x];
+                *dest++ = 0xff;
+            }
+        }
+
+        for (i = 0; i < 3; i++)
+            src[i] += srcStride[i];
+    }
+}
+
+static int planarRgbToRgbWrapper(SwsContext *c, const uint8_t *src[],
+                                 int srcStride[], int srcSliceY, int srcSliceH,
+                                 uint8_t *dst[], int dstStride[])
+{
+    int alpha_first = 0;
+    if (c->srcFormat != PIX_FMT_GBRP) {
+        av_log(c, AV_LOG_ERROR, "unsupported planar RGB conversion %s -> %s\n",
+               av_get_pix_fmt_name(c->srcFormat),
+               av_get_pix_fmt_name(c->dstFormat));
+        return srcSliceH;
+    }
+
+    switch (c->dstFormat) {
+    case PIX_FMT_BGR24:
+        gbr24ptopacked24((const uint8_t *[]) { src[1], src[0], src[2] },
+                         (int []) { srcStride[1], srcStride[0], srcStride[2] },
+                         dst[0] + srcSliceY * dstStride[0], dstStride[0],
+                         srcSliceH, c->srcW);
+        break;
+
+    case PIX_FMT_RGB24:
+        gbr24ptopacked24((const uint8_t *[]) { src[2], src[0], src[1] },
+                         (int []) { srcStride[2], srcStride[0], srcStride[1] },
+                         dst[0] + srcSliceY * dstStride[0], dstStride[0],
+                         srcSliceH, c->srcW);
+        break;
+
+    case PIX_FMT_ARGB:
+        alpha_first = 1;
+    case PIX_FMT_RGBA:
+        gbr24ptopacked32((const uint8_t *[]) { src[2], src[0], src[1] },
+                         (int []) { srcStride[2], srcStride[0], srcStride[1] },
+                         dst[0] + srcSliceY * dstStride[0], dstStride[0],
+                         srcSliceH, alpha_first, c->srcW);
+        break;
+
+    case PIX_FMT_ABGR:
+        alpha_first = 1;
+    case PIX_FMT_BGRA:
+        gbr24ptopacked32((const uint8_t *[]) { src[1], src[0], src[2] },
+                         (int []) { srcStride[1], srcStride[0], srcStride[2] },
+                         dst[0] + srcSliceY * dstStride[0], dstStride[0],
+                         srcSliceH, alpha_first, c->srcW);
+        break;
+
+    default:
+        av_log(c, AV_LOG_ERROR,
+               "unsupported planar RGB conversion %s -> %s\n",
+               av_get_pix_fmt_name(c->srcFormat),
+               av_get_pix_fmt_name(c->dstFormat));
+    }
+
+    return srcSliceH;
+}
+
 #define isRGBA32(x) (            \
            (x) == PIX_FMT_ARGB   \
         || (x) == PIX_FMT_RGBA   \
@@ -797,6 +899,9 @@ void ff_get_unscaled_swscale(SwsContext *c)
         && (!needsDither || (c->flags&(SWS_FAST_BILINEAR|SWS_POINT))))
         c->swScale= rgbToRgbWrapper;
 
+    if (isPlanarRGB(srcFormat) && isPackedRGB(dstFormat))
+        c->swScale = planarRgbToRgbWrapper;
+
     /* bswap 16 bits per pixel/component packed formats */
     if (IS_DIFFERENT_ENDIANESS(srcFormat, dstFormat, PIX_FMT_BGR444) ||
         IS_DIFFERENT_ENDIANESS(srcFormat, dstFormat, PIX_FMT_BGR48)  ||