[FFmpeg-devel] [PATCH] swscale: Add support for unscaled 8-bit Packed RGB -> Planar RGB

[Derek Buitenhuis]

Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
---
 libswscale/swscale_unscaled.c |  119 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 119 insertions(+)

diff --git a/libswscale/swscale_unscaled.c b/libswscale/swscale_unscaled.c
index 55cda5d..7599779 100644
--- a/libswscale/swscale_unscaled.c
+++ b/libswscale/swscale_unscaled.c
@@ -488,6 +488,122 @@ static int planarRgbToRgbWrapper(SwsContext *c, const uint8_t *src[],
     return srcSliceH;
 }
 
+static void packed24togbr24p(const uint8_t *src, int srcStride,
+                             uint8_t *dst[], int dstStride[], int srcSliceH,
+                             int width)
+{
+    uint8_t *dest[3];
+    int x, h;
+
+    dest[0] = dst[0];
+    dest[1] = dst[1];
+    dest[2] = dst[2];
+
+    for (h = 0; h < srcSliceH; h++) {
+        for (x = 0; x < width; x++) {
+            dest[0][x] = *src++;
+            dest[1][x] = *src++;
+            dest[2][x] = *src++;
+        }
+        src     += srcStride - width * 3;
+        dest[0] += dstStride[0];
+        dest[1] += dstStride[1];
+        dest[2] += dstStride[2];
+    }
+}
+
+static void packed32togbr24p(const uint8_t *src, int srcStride,
+                             uint8_t *dst[], int dstStride[], int srcSliceH,
+                             int alpha_first, int width)
+{
+    uint8_t *dest[4];
+    int x, h;
+
+    dest[0] = dst[0];
+    dest[1] = dst[1];
+    dest[2] = dst[2];
+
+    if (alpha_first) {
+        for (h = 0; h < srcSliceH; h++) {
+            for (x = 0; x < width; x++) {
+                src++;
+                dest[0][x] = *src++;
+                dest[1][x] = *src++;
+                dest[2][x] = *src++;
+            }
+            src     += srcStride - width * 4;
+            dest[0] += dstStride[0];
+            dest[1] += dstStride[1];
+            dest[2] += dstStride[2];
+        }
+    } else {
+        for (h = 0; h < srcSliceH; h++) {
+            for (x = 0; x < width; x++) {
+                dest[0][x] = *src++;
+                dest[1][x] = *src++;
+                dest[2][x] = *src++;
+                src++;
+            }
+            src     += srcStride - width * 4;
+            dest[0] += dstStride[0];
+            dest[1] += dstStride[1];
+            dest[2] += dstStride[2];
+        }
+    }
+}
+
+static int rgbToPlanarRgbWrapper(SwsContext *c, const uint8_t *src[],
+                                 int srcStride[], int srcSliceY, int srcSliceH,
+                                 uint8_t *dst[], int dstStride[])
+{
+    int alpha_first = 0;
+    int stride102[] = { dstStride[1], dstStride[0], dstStride[2] };
+    int stride201[] = { dstStride[2], dstStride[0], dstStride[1] };
+    uint8_t *dst102[] = { dst[1] + srcSliceY * dstStride[1],
+                          dst[0] + srcSliceY * dstStride[0],
+                          dst[2] + srcSliceY * dstStride[2] };
+    uint8_t *dst201[] = { dst[2] + srcSliceY * dstStride[2],
+                          dst[0] + srcSliceY * dstStride[0],
+                          dst[1] + srcSliceY * dstStride[1] };
+
+    if (c->dstFormat != 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->srcFormat) {
+    case PIX_FMT_RGB24:
+        packed24togbr24p((const uint8_t *) src[0], srcStride[0],
+                         dst201, stride201, srcSliceH, c->srcW);
+        break;
+    case PIX_FMT_BGR24:
+        packed24togbr24p((const uint8_t *) src[0], srcStride[0],
+                         dst102, stride102, srcSliceH, c->srcW);
+        break;
+    case PIX_FMT_ARGB:
+        alpha_first = 1;
+    case PIX_FMT_RGBA:
+        packed32togbr24p((const uint8_t *) src[0], srcStride[0], dst201,
+                         stride201, alpha_first, srcSliceH, c->srcW);
+        break;
+    case PIX_FMT_ABGR:
+        alpha_first = 1;
+    case PIX_FMT_BGRA:
+        packed32togbr24p((const uint8_t *) src[0], srcStride[0], dst102,
+                         stride102, alpha_first, srcSliceH, 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) == AV_PIX_FMT_ARGB   \
         || (x) == AV_PIX_FMT_RGBA   \
@@ -970,6 +1086,9 @@ void ff_get_unscaled_swscale(SwsContext *c)
 
     if (srcFormat == AV_PIX_FMT_GBR24P && isPlanar(srcFormat) && isByteRGB(dstFormat))
         c->swScale = planarRgbToRgbWrapper;
+    
+    if (srcFormat == AV_PIX_FMT_GBRP && isPlanarRGB(dstFormat) && isByteRGB(dstFormat))
+        c->swScale = rgbToPlanarRgbWrapper;
 
     /* bswap 16 bits per pixel/component packed formats */
     if (IS_DIFFERENT_ENDIANESS(srcFormat, dstFormat, AV_PIX_FMT_BGR444) ||
-- 
1.7.10.4