diff mbox series

[v3,11/24] media: v4l2: Reorder field reflist

Message ID 20220405204426.259074-12-nicolas.dufresne@collabora.com (mailing list archive)
State New, archived
Headers show
Series [v3,01/24] media: doc: Document dual use of H.264 pic_num/frame_num | expand

Commit Message

Nicolas Dufresne April 5, 2022, 8:44 p.m. UTC
As per spec, the field reflist requires interleaving top and bottom
field in a specific way that does not fit inside the sort operation.
The process consist of alternating references parity, starting with
a reference of the same parity as the current picture. This
processs is done twice, once for short term references and a second
time for the long term references.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Sebastian Fricke <sebastian.fricke@collabora.com>
---
 drivers/media/v4l2-core/v4l2-h264.c | 42 +++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

Comments

Hans Verkuil April 22, 2022, 7:31 a.m. UTC | #1
On 05/04/2022 22:44, Nicolas Dufresne wrote:
> As per spec, the field reflist requires interleaving top and bottom
> field in a specific way that does not fit inside the sort operation.
> The process consist of alternating references parity, starting with
> a reference of the same parity as the current picture. This
> processs is done twice, once for short term references and a second
> time for the long term references.
> 
> Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
> Reviewed-by: Sebastian Fricke <sebastian.fricke@collabora.com>
> ---
>  drivers/media/v4l2-core/v4l2-h264.c | 42 +++++++++++++++++++++++++++++
>  1 file changed, 42 insertions(+)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c
> index 7e1eba03099a..d2d1f3bed7e8 100644
> --- a/drivers/media/v4l2-core/v4l2-h264.c
> +++ b/drivers/media/v4l2-core/v4l2-h264.c
> @@ -244,6 +244,40 @@ static int v4l2_h264_b1_ref_list_cmp(const void *ptra, const void *ptrb,
>  	return poca < pocb ? -1 : 1;
>  }
>  
> +/*
> + * The references need to be reordered so that references are alternating
> + * between top and bottom field references starting with the current picture
> + * parity. This has to be * done for short term and long term references
                             ^
Spurious *.

Regards,

	Hans

> + * separately.
> + */
> +static void reorder_field_reflist(const struct v4l2_h264_reflist_builder *b,
> +				  struct v4l2_h264_reference *reflist)
> +{
> +	struct v4l2_h264_reference tmplist[V4L2_H264_REF_LIST_LEN];
> +	u8 lt, i = 0, j = 0, k = 0;
> +
> +	memcpy(tmplist, reflist, sizeof(tmplist[0]) * b->num_valid);
> +
> +	for (lt = 0; lt <= 1; lt++) {
> +		do {
> +			for (; i < b->num_valid && b->refs[tmplist[i].index].longterm == lt; i++) {
> +				if (tmplist[i].fields == b->cur_pic_fields) {
> +					reflist[k++] = tmplist[i++];
> +					break;
> +				}
> +			}
> +
> +			for (; j < b->num_valid && b->refs[tmplist[j].index].longterm == lt; j++) {
> +				if (tmplist[j].fields != b->cur_pic_fields) {
> +					reflist[k++] = tmplist[j++];
> +					break;
> +				}
> +			}
> +		} while ((i < b->num_valid && b->refs[tmplist[i].index].longterm == lt) ||
> +			 (j < b->num_valid && b->refs[tmplist[j].index].longterm == lt));
> +	}
> +}
> +
>  static char ref_type_to_char (u8 ref_type)
>  {
>  	switch (ref_type) {
> @@ -346,6 +380,9 @@ v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder,
>  	sort_r(reflist, builder->num_valid, sizeof(*reflist),
>  	       v4l2_h264_p_ref_list_cmp, NULL, builder);
>  
> +	if (builder->cur_pic_fields != V4L2_H264_FRAME_REF)
> +		reorder_field_reflist(builder, reflist);
> +
>  	print_ref_list_p(builder, reflist);
>  }
>  EXPORT_SYMBOL_GPL(v4l2_h264_build_p_ref_list);
> @@ -379,6 +416,11 @@ v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder,
>  	sort_r(b1_reflist, builder->num_valid, sizeof(*b1_reflist),
>  	       v4l2_h264_b1_ref_list_cmp, NULL, builder);
>  
> +	if (builder->cur_pic_fields != V4L2_H264_FRAME_REF) {
> +		reorder_field_reflist(builder, b0_reflist);
> +		reorder_field_reflist(builder, b1_reflist);
> +	}
> +
>  	if (builder->num_valid > 1 &&
>  	    !memcmp(b1_reflist, b0_reflist, builder->num_valid))
>  		swap(b1_reflist[0], b1_reflist[1]);
diff mbox series

Patch

diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c
index 7e1eba03099a..d2d1f3bed7e8 100644
--- a/drivers/media/v4l2-core/v4l2-h264.c
+++ b/drivers/media/v4l2-core/v4l2-h264.c
@@ -244,6 +244,40 @@  static int v4l2_h264_b1_ref_list_cmp(const void *ptra, const void *ptrb,
 	return poca < pocb ? -1 : 1;
 }
 
+/*
+ * The references need to be reordered so that references are alternating
+ * between top and bottom field references starting with the current picture
+ * parity. This has to be * done for short term and long term references
+ * separately.
+ */
+static void reorder_field_reflist(const struct v4l2_h264_reflist_builder *b,
+				  struct v4l2_h264_reference *reflist)
+{
+	struct v4l2_h264_reference tmplist[V4L2_H264_REF_LIST_LEN];
+	u8 lt, i = 0, j = 0, k = 0;
+
+	memcpy(tmplist, reflist, sizeof(tmplist[0]) * b->num_valid);
+
+	for (lt = 0; lt <= 1; lt++) {
+		do {
+			for (; i < b->num_valid && b->refs[tmplist[i].index].longterm == lt; i++) {
+				if (tmplist[i].fields == b->cur_pic_fields) {
+					reflist[k++] = tmplist[i++];
+					break;
+				}
+			}
+
+			for (; j < b->num_valid && b->refs[tmplist[j].index].longterm == lt; j++) {
+				if (tmplist[j].fields != b->cur_pic_fields) {
+					reflist[k++] = tmplist[j++];
+					break;
+				}
+			}
+		} while ((i < b->num_valid && b->refs[tmplist[i].index].longterm == lt) ||
+			 (j < b->num_valid && b->refs[tmplist[j].index].longterm == lt));
+	}
+}
+
 static char ref_type_to_char (u8 ref_type)
 {
 	switch (ref_type) {
@@ -346,6 +380,9 @@  v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder,
 	sort_r(reflist, builder->num_valid, sizeof(*reflist),
 	       v4l2_h264_p_ref_list_cmp, NULL, builder);
 
+	if (builder->cur_pic_fields != V4L2_H264_FRAME_REF)
+		reorder_field_reflist(builder, reflist);
+
 	print_ref_list_p(builder, reflist);
 }
 EXPORT_SYMBOL_GPL(v4l2_h264_build_p_ref_list);
@@ -379,6 +416,11 @@  v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder,
 	sort_r(b1_reflist, builder->num_valid, sizeof(*b1_reflist),
 	       v4l2_h264_b1_ref_list_cmp, NULL, builder);
 
+	if (builder->cur_pic_fields != V4L2_H264_FRAME_REF) {
+		reorder_field_reflist(builder, b0_reflist);
+		reorder_field_reflist(builder, b1_reflist);
+	}
+
 	if (builder->num_valid > 1 &&
 	    !memcmp(b1_reflist, b0_reflist, builder->num_valid))
 		swap(b1_reflist[0], b1_reflist[1]);