ImBuf: Add support for WebP image format

Currently only supports single image frames (no animation possible).

If quality slider is set to 100 then lossless compression will be used,
otherwise lossy compression is used.

Gives about 35% reduction of filesize  save when re-saving splash screens with lossless
compression.
Also saves much faster, up to 15x faster than PNG with a better compression ratio as a plus.

Note, this is currently left disabled until we have WebP libs (see T95206)

For testing precompiled libs can be downloaded from Google:
https://storage.googleapis.com/downloads.webmproject.org/releases/webp/index.html

Differential Revision: https://developer.blender.org/D1598

2 files changed, 40 insertions, 0 deletions

diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index 268239ed7b5..bb91b2f63f6 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -607,6 +607,10 @@ if(WITH_IMAGE_HDR)
   add_definitions(-DWITH_HDR)
 endif()
 
+if(WITH_IMAGE_WEBP)
+	add_definitions(-DWITH_WEBP)
+endif()
+
 if(WITH_CODEC_AVI)
   list(APPEND INC
     ../io/avi
diff --git a/source/blender/blenkernel/intern/image_format.cc b/source/blender/blenkernel/intern/image_format.cc
index 2b5712a1597..3ff0b3da963 100644
--- a/source/blender/blenkernel/intern/image_format.cc
+++ b/source/blender/blenkernel/intern/image_format.cc
@@ -120,6 +120,12 @@ int BKE_imtype_to_ftype(const char imtype, ImbFormatOptions *r_options)
     return IMB_FTYPE_JP2;
   }
 #endif
+#ifdef WITH_WEBP
+  if (imtype == R_IMF_IMTYPE_WEBP) {
+    r_options->quality = 90;
+    return IMB_FTYPE_WEBP;
+  }
+#endif
 
   r_options->quality = 90;
   return IMB_FTYPE_JPG;
@@ -177,6 +183,11 @@ char BKE_ftype_to_imtype(const int ftype, const ImbFormatOptions *options)
     return R_IMF_IMTYPE_JP2;
   }
 #endif
+#ifdef WITH_WEBP
+  if (ftype == IMB_FTYPE_WEBP) {
+    return R_IMF_IMTYPE_WEBP;
+  }
+#endif
 
   return R_IMF_IMTYPE_JPEG90;
 }
@@ -220,6 +231,7 @@ bool BKE_imtype_supports_quality(const char imtype)
     case R_IMF_IMTYPE_JPEG90:
     case R_IMF_IMTYPE_JP2:
     case R_IMF_IMTYPE_AVIJPEG:
+    case R_IMF_IMTYPE_WEBP:
       return true;
   }
   return false;
@@ -259,6 +271,7 @@ char BKE_imtype_valid_channels(const char imtype, bool write_file)
     case R_IMF_IMTYPE_DDS:
     case R_IMF_IMTYPE_JP2:
     case R_IMF_IMTYPE_DPX:
+    case R_IMF_IMTYPE_WEBP:
       chan_flag |= IMA_CHAN_FLAG_ALPHA;
       break;
   }
@@ -379,6 +392,11 @@ char BKE_imtype_from_arg(const char *imtype_arg)
     return R_IMF_IMTYPE_JP2;
   }
 #endif
+#ifdef WITH_WEBP
+  if (STREQ(imtype_arg, "WEBP")) {
+    return R_IMF_IMTYPE_WEBP;
+  }
+#endif
 
   return R_IMF_IMTYPE_INVALID;
 }
@@ -494,6 +512,12 @@ static bool do_add_image_extension(char *string,
     }
   }
 #endif
+#ifdef WITH_WEBP
+  else if (imtype == R_IMF_IMTYPE_WEBP) {
+    if (!BLI_path_extension_check(string, extension_test = ".webp"))
+      extension = extension_test;
+  }
+#endif
   else {  //   R_IMF_IMTYPE_AVIRAW, R_IMF_IMTYPE_AVIJPEG, R_IMF_IMTYPE_JPEG90 etc
     if (!(BLI_path_extension_check_n(string, extension_test = ".jpg", ".jpeg", nullptr))) {
       extension = extension_test;
@@ -732,6 +756,12 @@ void BKE_image_format_to_imbuf(ImBuf *ibuf, const ImageFormatData *imf)
     }
   }
 #endif
+#ifdef WITH_WEBP
+  else if (imtype == R_IMF_IMTYPE_WEBP) {
+    ibuf->ftype = IMB_FTYPE_WEBP;
+    ibuf->foptions.quality = quality;
+  }
+#endif
   else {
     /* #R_IMF_IMTYPE_JPEG90, etc. default to JPEG. */
     if (quality < 10) {
@@ -864,6 +894,12 @@ void BKE_image_format_from_imbuf(ImageFormatData *im_format, const ImBuf *imbuf)
     }
   }
 #endif
+#ifdef WITH_WEBP
+  else if (ftype == IMB_FTYPE_WEBP) {
+    im_format->imtype = R_IMF_IMTYPE_WEBP;
+    im_format->quality = quality;
+  }
+#endif
 
   else {
     im_format->imtype = R_IMF_IMTYPE_JPEG90;