[gimp] plug-ins: avoid converting TIFF channels.

[Jehan <jehanp src gnome org>]

commit ac8ad13f0a131d7efc2c07cf9f33817f45eec02d
Author: Jehan <jehan girinstud io>
Date:   Tue Jun 18 15:56:16 2019 +0200

    plug-ins: avoid converting TIFF channels.
    
    In GIMP, our channels (the ones from Channels dock) are always linear,
    and don't follow the image/profile TRC. When a TIFF image has extra
    channels (no semantic attached), we probably want to load the channel
    as-is, without converting the values. So let's assume that TIFF extra
    samples with "Unspecified data" in it are linear data. This way, their
    values goes copied straight into a channel.

 plug-ins/file-tiff/file-tiff-load.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/plug-ins/file-tiff/file-tiff-load.c b/plug-ins/file-tiff/file-tiff-load.c
index 645649b40d..5f0ecb102b 100644
--- a/plug-ins/file-tiff/file-tiff-load.c
+++ b/plug-ins/file-tiff/file-tiff-load.c
@@ -1068,9 +1068,9 @@ load_image (GFile        *file,
                                                 100.0, &color);
               gimp_image_insert_channel (*image, channel[i].ID, -1, 0);
               channel[i].buffer = gimp_drawable_get_buffer (channel[i].ID);
-              channel[i].format = babl_format_new (babl_model ("Y'"),
+              channel[i].format = babl_format_new (babl_model ("Y"),
                                                    type,
-                                                   babl_component ("Y'"),
+                                                   babl_component ("Y"),
                                                    NULL);
             }
         }