[MPlayer-dev-eng] [PATCH] vf_scale: add generic libswscale options support.

[Reimar Döffinger]

Allows setting any of the options exposed by libswscale,
in particular for example source and destination colorspace
range.
---
 DOCS/man/en/mplayer.1  |  5 +++++
 av_opts.c              |  6 ++++++
 cfg-common.h           |  1 +
 libmpcodecs/vf_scale.c | 25 ++++++++++++++++++++++++-
 libmpcodecs/vf_scale.h |  1 +
 5 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/DOCS/man/en/mplayer.1 b/DOCS/man/en/mplayer.1
index 7c01ca2c8..8e28024de 100644
--- a/DOCS/man/en/mplayer.1
+++ b/DOCS/man/en/mplayer.1
@@ -5405,6 +5405,11 @@ The description of the scale video filter has further information.
 .RE
 .
 .TP
+.B \-swsopts <software scaler options>
+Specify advanced software scaler options provided by libswscale.
+Set to "help" to get a list of supported options.
+.
+.TP
 .B \-vc <[\-|+]codec1,[\-|+]codec2,...[,]>
 Specify a priority list of video codecs to be used, according to their codec
 name in codecs.conf.
diff --git a/av_opts.c b/av_opts.c
index e10e92e90..30e049db2 100644
--- a/av_opts.c
+++ b/av_opts.c
@@ -30,6 +30,12 @@ int parse_avopts(void *v, char *str){

     if (!v)
         return -1;
+    if (!str)
+        return 0;
+    if (strcmp(str, "help") == 0) {
+        av_opt_show2(v, NULL, -1, 0);
+        return -1;
+    }

     start= str= strdup(str);

diff --git a/cfg-common.h b/cfg-common.h
index ca4e9c9cb..bfb815790 100644
--- a/cfg-common.h
+++ b/cfg-common.h
@@ -521,6 +521,7 @@ const m_option_t common_opts[] = {

     // scaling:
     {"sws", &sws_flags, CONF_TYPE_INT, 0, 0, 2, NULL},
+    {"swsopts", &sws_opts, CONF_TYPE_STRING, 0, 0, 0, NULL},
     {"ssf", scaler_filter_conf, CONF_TYPE_SUBCONFIG, 0, 0, 0, NULL},
     {"zoom", &softzoom, CONF_TYPE_FLAG, 0, 0, 1, NULL},
     {"nozoom", &softzoom, CONF_TYPE_FLAG, 0, 1, 0, NULL},
diff --git a/libmpcodecs/vf_scale.c b/libmpcodecs/vf_scale.c
index ef50261ea..e48a2ad45 100644
--- a/libmpcodecs/vf_scale.c
+++ b/libmpcodecs/vf_scale.c
@@ -32,9 +32,11 @@
 #include "fmt-conversion.h"
 #include "mpbswap.h"

+#include "libavutil/opt.h"
 #include "libswscale/swscale.h"
 #include "vf_scale.h"

+#include "av_opts.h"
 #include "m_option.h"
 #include "m_struct.h"

@@ -588,6 +590,7 @@ static int vf_open(vf_instance_t *vf, char *args){

 //global sws_flags from the command line
 int sws_flags=2;
+char *sws_opts;

 //global srcFilter
 static SwsFilter *src_filter= NULL;
@@ -648,6 +651,7 @@ struct SwsContext *sws_getContextFromCmdLine(int srcW, int srcH, int srcFormat,
 {
         int flags;
         SwsFilter *dstFilterParam, *srcFilterParam;
+        struct SwsContext *ctx;
         enum AVPixelFormat dfmt, sfmt;

         dfmt = imgfmt2pixfmt(dstFormat);
@@ -655,7 +659,26 @@ struct SwsContext *sws_getContextFromCmdLine(int srcW, int srcH, int srcFormat,
         if (srcFormat == IMGFMT_RGB8 || srcFormat == IMGFMT_BGR8) sfmt = AV_PIX_FMT_PAL8;
         sws_getFlagsAndFilterFromCmdLine(&flags, &srcFilterParam, &dstFilterParam);

-        return sws_getContext(srcW, srcH, sfmt, dstW, dstH, dfmt, flags, srcFilterParam, dstFilterParam, NULL);
+        ctx = sws_alloc_context();
+        if (!ctx) return NULL;
+        // set it first to allow swsopts to override/add to it
+        av_opt_set_int(ctx, "sws_flags", flags, 0);
+        if (parse_avopts(ctx, sws_opts) < 0) {
+            mp_msg(MSGT_VFILTER, MSGL_ERR, "Your options /%s/ look like gibberish to me pal.\n", sws_opts);
+            return NULL;
+        }
+        // always override these
+        av_opt_set_int(ctx, "srcw", srcW, 0);
+        av_opt_set_int(ctx, "srch", srcH, 0);
+        av_opt_set_int(ctx, "src_format", sfmt, 0);
+        av_opt_set_int(ctx, "dstw", dstW, 0);
+        av_opt_set_int(ctx, "dsth", dstH, 0);
+        av_opt_set_int(ctx, "dst_format", dfmt, 0);
+        if (sws_init_context(ctx, srcFilterParam, dstFilterParam) < 0) {
+            sws_freeContext(ctx);
+            return NULL;
+        }
+        return ctx;
 }

 /// An example of presets usage
diff --git a/libmpcodecs/vf_scale.h b/libmpcodecs/vf_scale.h
index 4de3b48ec..5890b5713 100644
--- a/libmpcodecs/vf_scale.h
+++ b/libmpcodecs/vf_scale.h
@@ -28,6 +28,7 @@ extern float sws_chr_sharpen;
 extern float sws_lum_sharpen;

 extern int sws_flags;
+extern char *sws_opts;

 struct SwsContext *sws_getContextFromCmdLine(int srcW, int srcH, int srcFormat, int dstW, int dstH, int dstFormat);

--
2.28.0