lavfi/curves: add support for Photoshop curves files (.acv).

1 files changed, 65 insertions, 0 deletions

diff --git a/libavfilter/vf_curves.c b/libavfilter/vf_curves.c
index 35a5af3946..dc012fa626 100644
--- a/libavfilter/vf_curves.c
+++ b/libavfilter/vf_curves.c
@@ -19,7 +19,10 @@
  */
 
 #include "libavutil/opt.h"
+#include "libavutil/bprint.h"
 #include "libavutil/eval.h"
+#include "libavutil/file.h"
+#include "libavutil/intreadwrite.h"
 #include "libavutil/avassert.h"
 #include "avfilter.h"
 #include "formats.h"
@@ -54,6 +57,7 @@ typedef struct {
     char *comp_points_str[NB_COMP + 1];
     char *comp_points_str_all;
     uint8_t graph[NB_COMP + 1][256];
+    char *psfile;
 } CurvesContext;
 
 #define OFFSET(x) offsetof(CurvesContext, x)
@@ -80,6 +84,7 @@ static const AVOption curves_options[] = {
     { "blue",  "set blue points coordinates",  OFFSET(comp_points_str[2]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
     { "b",     "set blue points coordinates",  OFFSET(comp_points_str[2]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
     { "all",   "set points coordinates for all components", OFFSET(comp_points_str_all), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
+    { "psfile", "set Photoshop curves file name", OFFSET(psfile), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
     { NULL }
 };
 
@@ -297,6 +302,60 @@ end:
     return ret;
 }
 
+static int parse_psfile(AVFilterContext *ctx, const char *fname)
+{
+    CurvesContext *curves = ctx->priv;
+    uint8_t *buf;
+    size_t size;
+    int i, ret, av_unused(version), nb_curves;
+    AVBPrint ptstr;
+    static const int comp_ids[] = {3, 0, 1, 2};
+
+    av_bprint_init(&ptstr, 0, AV_BPRINT_SIZE_AUTOMATIC);
+
+    ret = av_file_map(fname, &buf, &size, 0, NULL);
+    if (ret < 0)
+        return ret;
+
+#define READ16(dst) do {                \
+    if (size < 2)                       \
+        return AVERROR_INVALIDDATA;     \
+    dst = AV_RB16(buf);                 \
+    buf  += 2;                          \
+    size -= 2;                          \
+} while (0)
+
+    READ16(version);
+    READ16(nb_curves);
+    for (i = 0; i < FFMIN(nb_curves, FF_ARRAY_ELEMS(comp_ids)); i++) {
+        int nb_points, n;
+        av_bprint_clear(&ptstr);
+        READ16(nb_points);
+        for (n = 0; n < nb_points; n++) {
+            int y, x;
+            READ16(y);
+            READ16(x);
+            av_bprintf(&ptstr, "%f/%f ", x / 255., y / 255.);
+        }
+        if (*ptstr.str) {
+            char **pts = &curves->comp_points_str[comp_ids[i]];
+            if (!*pts) {
+                *pts = av_strdup(ptstr.str);
+                av_log(ctx, AV_LOG_DEBUG, "curves %d (intid=%d) [%d points]: [%s]\n",
+                       i, comp_ids[i], nb_points, *pts);
+                if (!*pts) {
+                    ret = AVERROR(ENOMEM);
+                    goto end;
+                }
+            }
+        }
+    }
+end:
+    av_bprint_finalize(&ptstr, NULL);
+    av_file_unmap(buf, size);
+    return ret;
+}
+
 static av_cold int init(AVFilterContext *ctx)
 {
     int i, j, ret;
@@ -317,6 +376,12 @@ static av_cold int init(AVFilterContext *ctx)
         }
     }
 
+    if (curves->psfile) {
+        ret = parse_psfile(ctx, curves->psfile);
+        if (ret < 0)
+            return ret;
+    }
+
     if (curves->preset != PRESET_NONE) {
 #define SET_COMP_IF_NOT_SET(n, name) do {                           \
     if (!pts[n] && curves_presets[curves->preset].name) {           \