[FFmpeg-devel] [PATCH 2/2] lavfi/vf_overlay: support NV12

[Rodger Combs]

---
 libavfilter/vf_overlay.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/libavfilter/vf_overlay.c b/libavfilter/vf_overlay.c
index 71f4db7..e01b924 100644
--- a/libavfilter/vf_overlay.c
+++ b/libavfilter/vf_overlay.c
@@ -125,6 +125,7 @@ typedef struct OverlayContext {
     int main_pix_step[4];       ///< steps per pixel for each plane of the main output
     int overlay_pix_step[4];    ///< steps per pixel for each plane of the overlay
     int hsub, vsub;             ///< chroma subsampling values
+    const AVPixFmtDescriptor *main_desc;
 
     double var_values[VAR_VARS_NB];
     char *x_expr, *y_expr;
@@ -213,7 +214,7 @@ static int query_formats(AVFilterContext *ctx)
 
     /* overlay formats contains alpha, for avoiding conversion with alpha information loss */
     static const enum AVPixelFormat main_pix_fmts_yuv420[] = {
-        AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVA420P, AV_PIX_FMT_NONE
+        AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVA420P, AV_PIX_FMT_NV12, AV_PIX_FMT_NONE
     };
     static const enum AVPixelFormat overlay_pix_fmts_yuv420[] = {
         AV_PIX_FMT_YUVA420P, AV_PIX_FMT_NONE
@@ -314,6 +315,8 @@ static int config_input_main(AVFilterLink *inlink)
     s->hsub = pix_desc->log2_chroma_w;
     s->vsub = pix_desc->log2_chroma_h;
 
+    s->main_desc = pix_desc;
+
     s->main_is_packed_rgb =
         ff_fill_rgba_map(s->main_rgba_map, inlink->format) >= 0;
     s->main_has_alpha = ff_fmt_is_in(inlink->format, alpha_pix_fmts);
@@ -530,12 +533,14 @@ static void blend_image(AVFilterContext *ctx,
 
             j = FFMAX(-yp, 0);
             sp = src->data[i] + j         * src->linesize[i];
-            dp = dst->data[i] + (yp+j)    * dst->linesize[i];
+            dp = dst->data[ol->main_desc->comp[i].plane]
+                              + (yp+j)    * dst->linesize[ol->main_desc->comp[i].plane]
+                              + ol->main_desc->comp[i].offset;
             ap = src->data[3] + (j<<vsub) * src->linesize[3];
 
             for (jmax = FFMIN(-yp + dst_hp, src_hp); j < jmax; j++) {
                 k = FFMAX(-xp, 0);
-                d = dp + xp+k;
+                d = dp + (xp+k) * ol->main_desc->comp[i].step;
                 s = sp + k;
                 a = ap + (k<<hsub);
 
@@ -574,10 +579,10 @@ static void blend_image(AVFilterContext *ctx,
                     }
                     *d = FAST_DIV255(*d * (255 - alpha) + *s * alpha);
                     s++;
-                    d++;
+                    d += ol->main_desc->comp[i].step;
                     a += 1 << hsub;
                 }
-                dp += dst->linesize[i];
+                dp += dst->linesize[ol->main_desc->comp[i].plane];
                 sp += src->linesize[i];
                 ap += (1 << vsub) * src->linesize[3];
             }
-- 
2.8.2