[FFmpeg-devel] [PATCH] lavf/tiff: add support for YUV deflate

[James Almer]

Signed-off-by: James Almer <jamrial at gmail.com>
---
Seems to work great with yuv deflate tiff images created with our tiff encoder

 libavcodec/tiff.c | 71 +++++++++++++++++++++++++++----------------------------
 1 file changed, 35 insertions(+), 36 deletions(-)

diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index 73bf828..7acfe7b 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -283,6 +283,34 @@ static int deinvert_buffer(TiffContext *s, const uint8_t *src, int size)
     return 0;
 }
 
+static void unpack_yuv(TiffContext *s, AVFrame *p,
+                       const uint8_t *src, int lnum)
+{
+    int i, j, k;
+    int w       = (s->width - 1) / s->subsampling[0] + 1;
+    uint8_t *pu = &p->data[1][lnum / s->subsampling[1] * p->linesize[1]];
+    uint8_t *pv = &p->data[2][lnum / s->subsampling[1] * p->linesize[2]];
+    if (s->width % s->subsampling[0] || s->height % s->subsampling[1]) {
+        for (i = 0; i < w; i++) {
+            for (j = 0; j < s->subsampling[1]; j++)
+                for (k = 0; k < s->subsampling[0]; k++)
+                    p->data[0][FFMIN(lnum + j, s->height-1) * p->linesize[0] +
+                               FFMIN(i * s->subsampling[0] + k, s->width-1)] = *src++;
+            *pu++ = *src++;
+            *pv++ = *src++;
+        }
+    }else{
+        for (i = 0; i < w; i++) {
+            for (j = 0; j < s->subsampling[1]; j++)
+                for (k = 0; k < s->subsampling[0]; k++)
+                    p->data[0][(lnum + j) * p->linesize[0] +
+                               i * s->subsampling[0] + k] = *src++;
+            *pu++ = *src++;
+            *pv++ = *src++;
+        }
+    }
+}
+
 #if CONFIG_ZLIB
 static int tiff_uncompress(uint8_t *dst, unsigned long *len, const uint8_t *src,
                            int size)
@@ -305,9 +333,9 @@ static int tiff_uncompress(uint8_t *dst, unsigned long *len, const uint8_t *src,
     return zret == Z_STREAM_END ? Z_OK : zret;
 }
 
-static int tiff_unpack_zlib(TiffContext *s, uint8_t *dst, int stride,
+static int tiff_unpack_zlib(TiffContext *s, AVFrame *p, uint8_t *dst, int stride,
                             const uint8_t *src, int size,
-                            int width, int lines)
+                            int width, int lines, int strip_start)
 {
     uint8_t *zbuf;
     unsigned long outlen;
@@ -338,6 +366,10 @@ static int tiff_unpack_zlib(TiffContext *s, uint8_t *dst, int stride,
         } else {
             memcpy(dst, src, width);
         }
+        if (s->photometric == TIFF_PHOTOMETRIC_YCBCR) {
+            unpack_yuv(s, p, dst, strip_start + line);
+            line += s->subsampling[1] - 1;
+        }
         dst += stride;
         src += width;
     }
@@ -383,35 +415,6 @@ static int tiff_unpack_fax(TiffContext *s, uint8_t *dst, int stride,
     return ret;
 }
 
-static void unpack_yuv(TiffContext *s, AVFrame *p,
-                       const uint8_t *src, int lnum)
-{
-    int i, j, k;
-    int w       = (s->width - 1) / s->subsampling[0] + 1;
-    uint8_t *pu = &p->data[1][lnum / s->subsampling[1] * p->linesize[1]];
-    uint8_t *pv = &p->data[2][lnum / s->subsampling[1] * p->linesize[2]];
-    if (s->width % s->subsampling[0] || s->height % s->subsampling[1]) {
-        for (i = 0; i < w; i++) {
-            for (j = 0; j < s->subsampling[1]; j++)
-                for (k = 0; k < s->subsampling[0]; k++)
-                    p->data[0][FFMIN(lnum + j, s->height-1) * p->linesize[0] +
-                               FFMIN(i * s->subsampling[0] + k, s->width-1)] = *src++;
-            *pu++ = *src++;
-            *pv++ = *src++;
-        }
-    }else{
-        for (i = 0; i < w; i++) {
-            for (j = 0; j < s->subsampling[1]; j++)
-                for (k = 0; k < s->subsampling[0]; k++)
-                    p->data[0][(lnum + j) * p->linesize[0] +
-                               i * s->subsampling[0] + k] = *src++;
-            *pu++ = *src++;
-            *pv++ = *src++;
-        }
-    }
-}
-
-
 static int tiff_unpack_strip(TiffContext *s, AVFrame *p, uint8_t *dst, int stride,
                              const uint8_t *src, int size, int strip_start, int lines)
 {
@@ -443,12 +446,8 @@ static int tiff_unpack_strip(TiffContext *s, AVFrame *p, uint8_t *dst, int strid
     }
 
     if (s->compr == TIFF_DEFLATE || s->compr == TIFF_ADOBE_DEFLATE) {
-        if (is_yuv) {
-            av_log(s->avctx, AV_LOG_ERROR, "YUV deflate is unsupported");
-            return AVERROR_PATCHWELCOME;
-        }
 #if CONFIG_ZLIB
-        return tiff_unpack_zlib(s, dst, stride, src, size, width, lines);
+        return tiff_unpack_zlib(s, p, dst, stride, src, size, width, lines, strip_start);
 #else
         av_log(s->avctx, AV_LOG_ERROR,
                "zlib support not enabled, "
-- 
1.8.5.5