v4l2slvp8dec: Flip the meaning of segment_feature_mode

In section 9.3.4 a), segment_feature_mode have 0 for absolute and 1 for delta,
while in 19.2, it says the opposite. But the reference code, which usually
rules over the text state that 1 means absolute:

 if (hdr->update_data)
 {
     hdr->abs = bool_get_bit(bool);

And uses it with that meaning to decide weither to override the existing value
or just add the detla. This fixes multiple decoding issues.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1245>

diff --git a/sys/v4l2codecs/gstv4l2codecvp8dec.c b/sys/v4l2codecs/gstv4l2codecvp8dec.c
index 92c102c..4fab7fa 100644 (file)
--- a/sys/v4l2codecs/gstv4l2codecvp8dec.c
+++ b/sys/v4l2codecs/gstv4l2codecvp8dec.c
@@ -264,7 +264,7 @@ gst_v4l2_codec_vp8_dec_fill_segment_header (struct v4l2_vp8_segment_header
     (segmentation->segmentation_enabled ? V4L2_VP8_SEGMENT_HEADER_FLAG_ENABLED : 0) |
     (segmentation->update_mb_segmentation_map ? V4L2_VP8_SEGMENT_HEADER_FLAG_UPDATE_MAP : 0) |
     (segmentation->update_segment_feature_data ? V4L2_VP8_SEGMENT_HEADER_FLAG_UPDATE_FEATURE_DATA : 0) |
-    (segmentation->segment_feature_mode == 1 ? V4L2_VP8_SEGMENT_HEADER_FLAG_DELTA_VALUE_MODE : 0);
+    (segmentation->segment_feature_mode ? 0 : V4L2_VP8_SEGMENT_HEADER_FLAG_DELTA_VALUE_MODE);
   /* *INDENT-ON* */
 
   for (i = 0; i < 4; i++) {