[FFmpeg-devel] [PATCH 11/12] avfilter/vf_setparams: add alpha_mode parameter

[Niklas Haas]

From: Niklas Haas <git at haasn.dev>

---
 doc/filters.texi           | 13 +++++++++++++
 libavfilter/vf_setparams.c | 10 ++++++++++
 2 files changed, 23 insertions(+)

diff --git a/doc/filters.texi b/doc/filters.texi
index fa23c10b2d..6e8272fd81 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -22231,6 +22231,19 @@ Keep the same chroma location (default).
 @item bottomleft
 @item bottom
 @end table
+
+ at item alpha_mode
+Set the alpha moda.
+Available values are:
+
+ at table @samp
+ at item auto
+Keep the same alpha mode (default).
+
+ at item unspecified, unknown
+ at item premultiplied
+ at item straight
+ at end table
 @end table
 
 @section sharpen_npp
diff --git a/libavfilter/vf_setparams.c b/libavfilter/vf_setparams.c
index 34583b1d10..01902da763 100644
--- a/libavfilter/vf_setparams.c
+++ b/libavfilter/vf_setparams.c
@@ -42,6 +42,7 @@ typedef struct SetParamsContext {
     int color_trc;
     int colorspace;
     int chroma_location;
+    int alpha_mode;
 } SetParamsContext;
 
 #define OFFSET(x) offsetof(SetParamsContext, x)
@@ -131,6 +132,13 @@ static const AVOption setparams_options[] = {
     {"top",                              NULL, 0, AV_OPT_TYPE_CONST, {.i64=AVCHROMA_LOC_TOP},         0, 0, FLAGS, .unit = "chroma_location"},
     {"bottomleft",                       NULL, 0, AV_OPT_TYPE_CONST, {.i64=AVCHROMA_LOC_BOTTOMLEFT},  0, 0, FLAGS, .unit = "chroma_location"},
     {"bottom",                           NULL, 0, AV_OPT_TYPE_CONST, {.i64=AVCHROMA_LOC_BOTTOM},      0, 0, FLAGS, .unit = "chroma_location"},
+
+    {"alpha_mode", "select alpha moda", OFFSET(alpha_mode), AV_OPT_TYPE_INT, {.i64=-1}, -1, AVALPHA_MODE_NB-1, FLAGS, .unit = "alpha_mode"},
+    {"auto", "keep the same alpha mode",  0, AV_OPT_TYPE_CONST, {.i64=-1},                              0, 0, FLAGS, .unit = "alpha_mode"},
+    {"unspecified",                      NULL, 0, AV_OPT_TYPE_CONST, {.i64=AVALPHA_MODE_UNSPECIFIED},   0, 0, FLAGS, .unit = "alpha_mode"},
+    {"unknown",                          NULL, 0, AV_OPT_TYPE_CONST, {.i64=AVALPHA_MODE_UNSPECIFIED},   0, 0, FLAGS, .unit = "alpha_mode"},
+    {"premultiplied",                    NULL, 0, AV_OPT_TYPE_CONST, {.i64=AVALPHA_MODE_PREMULTIPLIED}, 0, 0, FLAGS, .unit = "alpha_mode"},
+    {"straight",                         NULL, 0, AV_OPT_TYPE_CONST, {.i64=AVALPHA_MODE_STRAIGHT},      0, 0, FLAGS, .unit = "alpha_mode"},
     {NULL}
 };
 
@@ -198,6 +206,8 @@ FF_ENABLE_DEPRECATION_WARNINGS
         frame->colorspace = s->colorspace;
     if (s->chroma_location >= 0)
         frame->chroma_location = s->chroma_location;
+    if (s->alpha_mode >= 0)
+        frame->alpha_mode = s->alpha_mode;
 
     return ff_filter_frame(ctx->outputs[0], frame);
 }
-- 
2.47.0