From 40ffd5468a1e39b715069e255ec5ed9a3acf2485 Mon Sep 17 00:00:00 2001 From: Nicolas Dufresne Date: Fri, 13 May 2022 22:29:09 +0200 Subject: [PATCH] media: v4l2: Reorder field reflist 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 Reviewed-by: Sebastian Fricke Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- 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 fe215035d9e82..72bd64f651981 100644 --- a/drivers/media/v4l2-core/v4l2-h264.c +++ b/drivers/media/v4l2-core/v4l2-h264.c @@ -250,6 +250,40 @@ 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) { @@ -360,6 +394,9 @@ 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); @@ -393,6 +430,11 @@ 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]); -- 2.39.5