[FFmpeg-devel] [RFC][PATCH 1/2] pixdesc: add av_find_pix_fmt()

[Paul B Mahol]

Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
 libavutil/pixdesc.c |   37 +++++++++++++++++++++++++++++++++++++
 libavutil/pixdesc.h |    8 ++++++++
 2 files changed, 45 insertions(+), 0 deletions(-)

diff --git a/libavutil/pixdesc.c b/libavutil/pixdesc.c
index 233b217..83f256b 100644
--- a/libavutil/pixdesc.c
+++ b/libavutil/pixdesc.c
@@ -1272,3 +1272,40 @@ char *av_get_pix_fmt_string (char *buf, int buf_size, enum PixelFormat pix_fmt)
 
     return buf;
 }
+
+enum PixelFormat av_find_pix_fmt(const AVPixFmtDescriptor *pixdesc, int flags)
+{
+    enum PixelFormat pix_fmt;
+    int i;
+
+    for (pix_fmt = 0; pix_fmt < PIX_FMT_NB; pix_fmt++) {
+        const AVPixFmtDescriptor *c = &av_pix_fmt_descriptors[pix_fmt];
+
+        if ((c->flags         != pixdesc->flags)         ||
+            (c->nb_components != pixdesc->nb_components) ||
+            (c->log2_chroma_w != pixdesc->log2_chroma_w) ||
+            (c->log2_chroma_h != pixdesc->log2_chroma_h))
+            continue;
+        for (i = 0; i < pixdesc->nb_components; i++) {
+            if (flags &  1)
+                if (c->comp[i].plane != pixdesc->comp[i].plane)
+                    break;
+            if (flags &  2)
+                if (c->comp[i].step_minus1 != pixdesc->comp[i].step_minus1)
+                    break;
+            if (flags &  4)
+                if (c->comp[i].offset_plus1 != pixdesc->comp[i].offset_plus1)
+                    break;
+            if (flags &  8)
+                if (c->comp[i].shift != pixdesc->comp[i].shift)
+                    break;
+            if (flags & 16)
+                if (c->comp[i].depth_minus1 != pixdesc->comp[i].depth_minus1)
+                    break;
+        }
+        if (i == pixdesc->nb_components)
+            return pix_fmt;
+    }
+
+    return PIX_FMT_NONE;
+}
diff --git a/libavutil/pixdesc.h b/libavutil/pixdesc.h
index f1a2dde..e90f194 100644
--- a/libavutil/pixdesc.h
+++ b/libavutil/pixdesc.h
@@ -183,4 +183,12 @@ char *av_get_pix_fmt_string (char *buf, int buf_size, enum PixelFormat pix_fmt);
  */
 int av_get_bits_per_pixel(const AVPixFmtDescriptor *pixdesc);
 
+/**
+ * Return the pixel format corresponding to pixdesc.
+ *
+ * @param flags the flags which describe what parameters in AVComponentDescriptor
+ * are to be compared.
+ */
+enum PixelFormat av_find_pix_fmt(const AVPixFmtDescriptor *pixdesc, int flags);
+
 #endif /* AVUTIL_PIXDESC_H */
-- 
1.7.7