feat: Support display color space interop IDs in I/O

src/bmp.imageio/bmpinput.cpp

@@ -8,6 +8,8 @@
 #include <OpenImageIO/fmath.h>
 #include <OpenImageIO/imageio.h>
 
+#include "imageio_pvt.h"
+
 #include "bmp_pvt.h"
 
 OIIO_PLUGIN_NAMESPACE_BEGIN
@@ -33,6 +35,7 @@ class BmpInput final : public ImageInput {
                               void* data) override;
 
 private:
+    std::string m_image_state_default;  // Default image state for color space
     int64_t m_padded_scanline_size;
     int m_pad_size;
     bmp_pvt::BmpFileHeader m_bmp_header;
@@ -151,6 +154,9 @@ BmpInput::open(const std::string& name, ImageSpec& newspec,
     // this behavior off.
     bool monodetect = config["bmp:monochrome_detect"].get<int>(1);
 
+    m_image_state_default = config.get_string_attribute(
+        "oiio:ImageStateDefault");
+
     ioproxy_retrieve_from_config(config);
     if (!ioproxy_use_or_open(name))
         return false;
@@ -262,7 +268,9 @@ BmpInput::open(const std::string& name, ImageSpec& newspec,
     // Default presumption is that a BMP file is meant to look reasonable on a
     // display, so assume it's sRGB. This is not really correct -- see the
     // comments below.
-    m_spec.attribute("oiio:ColorSpace", "srgb_rec709_scene");
+    const bool erase_other_attributes = false;
+    pvt::set_colorspace_srgb(m_spec, m_image_state_default,
+                             erase_other_attributes);
 #if 0
     if (m_dib_header.size >= WINDOWS_V4
         && m_dib_header.cs_type == CSType::CalibratedRGB) {

src/cineon.imageio/cineoninput.cpp

@@ -182,13 +182,14 @@ CineonInput::open(const std::string& name, ImageSpec& newspec)
         // either grayscale or printing density
         if (!std::isinf(m_cin.header.Gamma()) && m_cin.header.Gamma() != 0.0f)
             // actual gamma value is read later on
-            set_colorspace_rec709_gamma(m_spec, float(m_cin.header.Gamma()));
+            pvt::set_colorspace_rec709_gamma(m_spec,
+                                             float(m_cin.header.Gamma()));
         break;
     }
 
     // gamma exponent
     if (!std::isinf(m_cin.header.Gamma()) && m_cin.header.Gamma() != 0.0f)
-        set_colorspace_rec709_gamma(m_spec, float(m_cin.header.Gamma()));
+        pvt::set_colorspace_rec709_gamma(m_spec, float(m_cin.header.Gamma()));
 #endif
 
     // general metadata

src/dds.imageio/ddsinput.cpp

@@ -15,6 +15,8 @@
 #include <OpenImageIO/parallel.h>
 #include <OpenImageIO/typedesc.h>
 
+#include "imageio_pvt.h"
+
 #include "dds_pvt.h"
 #define BCDEC_IMPLEMENTATION
 #include "bcdec.h"
@@ -59,8 +61,9 @@ class DDSInput final : public ImageInput {
                           void* data) override;
 
 private:
-    std::string m_filename;            ///< Stash the filename
-    std::vector<unsigned char> m_buf;  ///< Buffer the image pixels
+    std::string m_filename;             ///< Stash the filename
+    std::string m_image_state_default;  ///< Default image state for color space
+    std::vector<unsigned char> m_buf;   ///< Buffer the image pixels
     int m_subimage;
     int m_miplevel;
     int m_nchans;               ///< Number of colour channels in image
@@ -410,6 +413,8 @@ DDSInput::open(const std::string& name, ImageSpec& newspec,
                const ImageSpec& config)
 {
     ioproxy_retrieve_from_config(config);
+    m_image_state_default = config.get_string_attribute(
+        "oiio:ImageStateDefault");
     return open(name, newspec);
 }
 
@@ -828,7 +833,7 @@ DDSInput::seek_subimage(int subimage, int miplevel)
     if (bpp != 0)
         m_spec.attribute("oiio:BitsPerSample", bpp);
 
-    const char* colorspace = nullptr;
+    bool is_srgb = false;
 
     if (m_dds.fmt.fourCC == DDS_4CC_DX10) {
         switch (m_dx10.dxgiFormat) {
@@ -838,18 +843,17 @@ DDSInput::seek_subimage(int subimage, int miplevel)
         case DDS_FORMAT_BC7_UNORM_SRGB:
         case DDS_FORMAT_R8G8B8A8_UNORM_SRGB:
         case DDS_FORMAT_B8G8R8A8_UNORM_SRGB:
-        case DDS_FORMAT_B8G8R8X8_UNORM_SRGB:
-            colorspace = "srgb_rec709_scene";
-            break;
+        case DDS_FORMAT_B8G8R8X8_UNORM_SRGB: is_srgb = true; break;
         }
     }
 
-    // linear color space for HDR-ish images
-    if (colorspace == nullptr
-        && (basetype == TypeDesc::HALF || basetype == TypeDesc::FLOAT))
-        colorspace = "lin_rec709_scene";
-
-    m_spec.set_colorspace(colorspace);
+    if (is_srgb) {
+        pvt::set_colorspace_srgb(m_spec, m_image_state_default);
+    } else if (!is_srgb
+               && (basetype == TypeDesc::HALF || basetype == TypeDesc::FLOAT)) {
+        // linear color space for HDR-ish images
+        m_spec.set_colorspace("lin_rec709_scene");
+    }
 
     m_spec.default_channel_names();
     // Special case: if a 2-channel DDS RG or YA?

src/doc/builtinplugins.rst

@@ -60,7 +60,8 @@ tiles.
      - Version of the BMP file format
    * - ``oiio:ColorSpace``
      - string
-     - currently, it is always ``"sRGB"`` (we presume all BMP files are sRGB)
+     - currently, it is always ``"srgb_rec709_display"`` or
+       ``"srgb_rec709_scene"`` (we presume all BMP files are sRGB)
 
 **Configuration settings for BMP input**
 
@@ -86,6 +87,11 @@ options are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for BMP output**
 
@@ -210,6 +216,11 @@ attributes are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.    
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 Additionally, an integer ``dds:bc5normal`` global attribute is supported
 to control behaviour of images compressed in BC5/ATI2 compression format.
@@ -293,6 +304,11 @@ options are supported:
    * - ``oiio:subimages``
      - int
      - The number of "image elements" (subimages) in the file.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 
 **Configuration settings for DPX output**
@@ -617,6 +633,11 @@ options are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for GIF output**
 
@@ -726,6 +747,11 @@ options are supported:
        orientation of the image). If this hint is set to 0, the pixels will be
        left in their orientation as stored in the file, and the "Orientation"
        metadata will reflect that.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for HDR output**
 
@@ -806,6 +832,12 @@ attributes are supported:
        having Orientation 1). If zero, then libheif will not reorient the
        image and the Orientation metadata will be set to reflect the camera
        orientation.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
+
 
 **Configuration settings for HEIF output**
 
@@ -870,6 +902,11 @@ attributes are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.    
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for ICO output**
 
@@ -946,6 +983,11 @@ options are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for IFF output**
 
@@ -1062,6 +1104,11 @@ attributes are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for JPEG output**
 
@@ -1194,6 +1241,11 @@ attributes are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 If OpenJPH is installed, the reader will attempt to read the file first with 
 the OpenJPH library, and if that fails, it will fall back to the OpenJPEG library.
@@ -1301,6 +1353,11 @@ attributes are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for JPEG XL output**
 
@@ -1836,6 +1893,11 @@ attributes are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
    * - ``png:linear_premult``
      - int
      - If nonzero, will convert  or gamma-encoded values to linear color
@@ -2316,6 +2378,11 @@ options are supported:
        initialization. This populates the image attributes which depend on the
        pixel values.
        (Default: 0)
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 |
 
@@ -2423,6 +2490,11 @@ options are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for RLA output**
 
@@ -2673,6 +2745,11 @@ attributes are supported:
        cause the reader to leave alpha unassociated (versus the default of
        premultiplying color channels by alpha if the alpha channel is
        unassociated).
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for Targa output**
 
@@ -2841,6 +2918,11 @@ options are supported:
      - ptr
      - Pointer to a ``Filesystem::IOProxy`` that will handle the I/O, for
        example by reading from memory rather than the file system.
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for TIFF output**
 
@@ -3151,6 +3233,11 @@ attributes are supported:
      - If nonzero, will leave alpha unassociated (versus the default of
        premultiplying color channels by alpha if the alpha channel is
        unassociated).
+   * - ``oiio:ImageStateDefault``
+     - string
+     - If ``scene`` or ``display``, prefer to assign the image a scene or
+       display referred ``oiio:ColorSpace``. The default is ``display``,
+       while ``scene`` is more common for textures.
 
 **Configuration settings for WebP output**
 

src/doc/imagebufalgo.rst

@@ -2849,12 +2849,14 @@ Color space conversion
        .. code-tab:: c++
 
           ImageBuf Src ("tahoe.jpg");
-          ImageBuf Dst = ImageBufAlgo::colorconvert (Src, "sRGB", "acescg", true);
+          ImageBuf Dst = ImageBufAlgo::colorconvert (Src, "srgb_rec709_scene",
+                                                     "acescg", true);
 
        .. code-tab:: py
 
           Src = ImageBuf("tahoe.jpg")
-          Dst = ImageBufAlgo.colorconvert (Src, "sRGB", "acescg", True)
+          Dst = ImageBufAlgo.colorconvert (Src, "srgb_rec709_scene", "acescg",
+                                           True)
 
        .. code-tab:: bash oiiotool
 
@@ -2950,14 +2952,15 @@ Color space conversion
        .. code-tab:: c++
 
           ImageBuf Src ("tahoe.exr");
-          ImageBuf Dst = ImageBufAlgo::ociodisplay (Src, "sRGB", "Film", "lnf",
-                                                    "", true, "SHOT", "pe0012");
+          ImageBuf Dst = ImageBufAlgo::ociodisplay (Src, "srgb_rec709_scene",
+                                                    "Film", "lnf", "", true,
+                                                    "SHOT", "pe0012");
 
        .. code-tab:: py
 
           Src = ImageBuf("tahoe.jpg")
-          Dst = ImageBufAlgo.ociodisplay (Src, "sRGB", "Film", "lnf",
-                                          "", True, "SHOT", "pe0012")
+          Dst = ImageBufAlgo.ociodisplay (Src, "srgb_rec709_scene", "Film",
+                                          "lnf", "", True, "SHOT", "pe0012")
 
        .. code-tab:: bash oiiotool
 

src/doc/pythonbindings.rst

@@ -3610,7 +3610,8 @@ Color manipulation
     .. code-block:: python
 
         Src = ImageBuf ("tahoe.jpg")
-        Dst = ImageBufAlgo.colorconvert (Src, "sRGB", "scene_linear")
+        Dst = ImageBufAlgo.colorconvert (Src, "srgb_rec709_scene",
+                                         "scene_linear")
 
 
 
@@ -3660,7 +3661,7 @@ Color manipulation
     .. code-block:: python
 
         Src = ImageBuf ("tahoe.exr")
-        Dst = ImageBufAlgo.ociodisplay (Src, "sRGB", "Film", "lnf",
+        Dst = ImageBufAlgo.ociodisplay (Src, "srgb_rec709_scene", "Film", "lnf",
                                   context_key="SHOT", context_value="pe0012")