On Sat Sep 13 16:22:46 2025 +0530, Pavan Bobba wrote:
> Complete the "TODO: PROFILES" by enforcing profile-specific and
> monochrome constraints as defined by the AV1 specification
> (Section 5.5.2, "Color config syntax").
>
> The validator now checks:
>
> - Flags: reject any unknown bits set in sequence->flags
> - Profile range: only profiles 0..2 are valid
> - Profile 0: 8/10-bit only, subsampling must be 4:2:0 (sx=1, sy=1),
> monochrome allowed
> - Profile 1: 8/10-bit only, subsampling must be 4:4:4 (sx=0, sy=0),
> monochrome forbidden
> - Profile 2:
> * 8/10-bit: only 4:2:2 allowed (sx=1, sy=0)
> * 12-bit: 4:4:4 (sx=0, sy=0), 4:2:2 (sx=1, sy=0), or 4:2:0 (sx=1, sy=1)
> allowed
> - Monochrome path (all profiles except 1): forces subsampling_x=1,
> subsampling_y=1, separate_uv_delta_q=0
>
> These checks prevent userspace from providing invalid AV1 sequence
> headers that would otherwise be accepted, leading to undefined driver
> or hardware behavior.
>
> Signed-off-by: Pavan Bobba <[email protected]>
> Signed-off-by: Nicolas Dufresne <[email protected]>
> Signed-off-by: Hans Verkuil <[email protected]>
Patch committed.
Thanks,
Hans Verkuil
drivers/media/v4l2-core/v4l2-ctrls-core.c | 125 ++++++++++++++++++++++++------
1 file changed, 100 insertions(+), 25 deletions(-)
---
diff --git a/drivers/media/v4l2-core/v4l2-ctrls-core.c
b/drivers/media/v4l2-core/v4l2-ctrls-core.c
index 85d07ef44f62..7c660cd61e48 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls-core.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls-core.c
@@ -827,39 +827,114 @@ static int validate_av1_frame(struct v4l2_ctrl_av1_frame
*f)
return 0;
}
+/**
+ * validate_av1_sequence - validate AV1 sequence header fields
+ * @s: control struct from userspace
+ *
+ * Implements AV1 spec §5.5.2 color_config() checks that are
+ * possible with the current v4l2_ctrl_av1_sequence definition.
+ *
+ * TODO: extend validation once additional fields such as
+ * color_primaries, transfer_characteristics,
+ * matrix_coefficients, and chroma_sample_position
+ * are added to the uAPI.
+ *
+ * Returns 0 if valid, -EINVAL otherwise.
+ */
static int validate_av1_sequence(struct v4l2_ctrl_av1_sequence *s)
{
- if (s->flags &
- ~(V4L2_AV1_SEQUENCE_FLAG_STILL_PICTURE |
- V4L2_AV1_SEQUENCE_FLAG_USE_128X128_SUPERBLOCK |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_FILTER_INTRA |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_INTRA_EDGE_FILTER |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_INTERINTRA_COMPOUND |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_MASKED_COMPOUND |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_WARPED_MOTION |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_DUAL_FILTER |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_ORDER_HINT |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_JNT_COMP |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_REF_FRAME_MVS |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_SUPERRES |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_CDEF |
- V4L2_AV1_SEQUENCE_FLAG_ENABLE_RESTORATION |
- V4L2_AV1_SEQUENCE_FLAG_MONO_CHROME |
- V4L2_AV1_SEQUENCE_FLAG_COLOR_RANGE |
- V4L2_AV1_SEQUENCE_FLAG_SUBSAMPLING_X |
- V4L2_AV1_SEQUENCE_FLAG_SUBSAMPLING_Y |
- V4L2_AV1_SEQUENCE_FLAG_FILM_GRAIN_PARAMS_PRESENT |
- V4L2_AV1_SEQUENCE_FLAG_SEPARATE_UV_DELTA_Q))
- return -EINVAL;
+ const bool mono = s->flags & V4L2_AV1_SEQUENCE_FLAG_MONO_CHROME;
+ const bool sx = s->flags & V4L2_AV1_SEQUENCE_FLAG_SUBSAMPLING_X;
+ const bool sy = s->flags & V4L2_AV1_SEQUENCE_FLAG_SUBSAMPLING_Y;
+ const bool uv_dq = s->flags &
V4L2_AV1_SEQUENCE_FLAG_SEPARATE_UV_DELTA_Q;
- if (s->seq_profile == 1 && s->flags &
V4L2_AV1_SEQUENCE_FLAG_MONO_CHROME)
+ /* 1. Reject unknown flags */
+ if (s->flags &
+ ~(V4L2_AV1_SEQUENCE_FLAG_STILL_PICTURE |
+ V4L2_AV1_SEQUENCE_FLAG_USE_128X128_SUPERBLOCK |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_FILTER_INTRA |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_INTRA_EDGE_FILTER |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_INTERINTRA_COMPOUND |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_MASKED_COMPOUND |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_WARPED_MOTION |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_DUAL_FILTER |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_ORDER_HINT |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_JNT_COMP |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_REF_FRAME_MVS |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_SUPERRES |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_CDEF |
+ V4L2_AV1_SEQUENCE_FLAG_ENABLE_RESTORATION |
+ V4L2_AV1_SEQUENCE_FLAG_MONO_CHROME |
+ V4L2_AV1_SEQUENCE_FLAG_COLOR_RANGE |
+ V4L2_AV1_SEQUENCE_FLAG_SUBSAMPLING_X |
+ V4L2_AV1_SEQUENCE_FLAG_SUBSAMPLING_Y |
+ V4L2_AV1_SEQUENCE_FLAG_FILM_GRAIN_PARAMS_PRESENT |
+ V4L2_AV1_SEQUENCE_FLAG_SEPARATE_UV_DELTA_Q))
return -EINVAL;
- /* reserved */
+ /* 2. Profile range */
if (s->seq_profile > 2)
return -EINVAL;
- /* TODO: PROFILES */
+ /* 3. Monochrome shortcut */
+ if (mono) {
+ /* Profile 1 forbids monochrome */
+ if (s->seq_profile == 1)
+ return -EINVAL;
+
+ /* Mono â subsampling must look like 4:0:0: sx=1, sy=1 */
+ if (!sx || !sy)
+ return -EINVAL;
+
+ /* separate_uv_delta_q must be 0 */
+ if (uv_dq)
+ return -EINVAL;
+
+ return 0;
+ }
+
+ /* 4. Profile-specific rules */
+ switch (s->seq_profile) {
+ case 0:
+ /* Profile 0: only 8/10-bit, subsampling=4:2:0 (sx=1, sy=1) */
+ if (s->bit_depth != 8 && s->bit_depth != 10)
+ return -EINVAL;
+ if (!(sx && sy))
+ return -EINVAL;
+ break;
+
+ case 1:
+ /* Profile 1: only 8/10-bit, subsampling=4:4:4 (sx=0, sy=0) */
+ if (s->bit_depth != 8 && s->bit_depth != 10)
+ return -EINVAL;
+ if (sx || sy)
+ return -EINVAL;
+ break;
+
+ case 2:
+ /* Profile 2: 8/10/12-bit allowed */
+ if (s->bit_depth != 8 && s->bit_depth != 10 &&
+ s->bit_depth != 12)
+ return -EINVAL;
+
+ if (s->bit_depth == 12) {
+ if (!sx) {
+ /* 4:4:4 â sy must be 0 */
+ if (sy)
+ return -EINVAL;
+ } else {
+ /* sx=1 â sy=0 (4:2:2) or sy=1 (4:2:0) */
+ if (sy != 0 && sy != 1)
+ return -EINVAL;
+ }
+ } else {
+ /* 8/10-bit â only 4:2:2 allowed (sx=1, sy=0) */
+ if (!(sx && !sy))
+ return -EINVAL;
+ }
+ break;
+ }
+
return 0;
}
_______________________________________________
linuxtv-commits mailing list -- [email protected]
To unsubscribe send an email to [email protected]
