Dne nedelja, 29. maj 2022 ob 08:45:57 CEST je Jernej Škrabec napisal(a): > Dne petek, 27. maj 2022 ob 16:31:33 CEST je Benjamin Gaignard napisal(a): > > 'F.7.3.6.1 General slice segment header syntax' section of HEVC > > specification describes that a slice header always end aligned on > > byte boundary, therefore we only need to provide the data offset in bytes. > > > > Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx> > > --- > > Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst | 4 ++-- > > drivers/staging/media/sunxi/cedrus/cedrus_h265.c | 2 +- > > include/media/hevc-ctrls.h | 4 ++-- > > 3 files changed, 5 insertions(+), 5 deletions(-) > > > > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/ > Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > index 48a8825a001b..37079581c661 100644 > > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > @@ -3008,8 +3008,8 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - > > - ``bit_size`` > > - Size (in bits) of the current slice data. > > * - __u32 > > - - ``data_bit_offset`` > > - - Offset (in bits) to the video data in the current slice data. > > + - ``data_byte_offset`` > > + - Offset (in bytes) to the video data in the current slice data. > > * - __u32 > > - ``num_entry_point_offsets`` > > - Specifies the number of entry point offset syntax elements in the > slice header. > > diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c b/drivers/ > staging/media/sunxi/cedrus/cedrus_h265.c > > index 411601975124..835454239f73 100644 > > --- a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c > > +++ b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c > > @@ -405,7 +405,7 @@ static void cedrus_h265_setup(struct cedrus_ctx *ctx, > > /* Initialize bitstream access. */ > > cedrus_write(dev, VE_DEC_H265_TRIGGER, > VE_DEC_H265_TRIGGER_INIT_SWDEC); > > > > - cedrus_h265_skip_bits(dev, slice_params->data_bit_offset); > > + cedrus_h265_skip_bits(dev, slice_params->data_byte_offset * 8); > > While it's true that actual data starts on 8-bit aligned address, Cedrus for > some reason needs offset which points at the end of the header, before > alignment. There is very simple way to determine that, but unfortunately this > means reading source buffer. > > In short, above code won't work. I'll provide a fix. Please include following fix http://ix.io/3Z8x otherwise Cedrus will fail to decode slice. Other than fix in previous e-mail and this one, code looks good and I'll be able to add missing functionality to Cedrus without much trouble in follow up series. Best regards, Jernej > > > > > /* Bitstream parameters. */ > > > > diff --git a/include/media/hevc-ctrls.h b/include/media/hevc-ctrls.h > > index 9abca1a75bd4..936ff693967b 100644 > > --- a/include/media/hevc-ctrls.h > > +++ b/include/media/hevc-ctrls.h > > @@ -312,7 +312,7 @@ struct v4l2_hevc_pred_weight_table { > > * V4L2_CTRL_FLAG_DYNAMIC_ARRAY flag must be set when using it. > > * > > * @bit_size: size (in bits) of the current slice data > > - * @data_bit_offset: offset (in bits) to the video data in the current slice > data > > + * @data_byte_offset: offset (in bytes) to the video data in the current > slice data > > * @num_entry_point_offsets: specifies the number of entry point offset syntax > > * elements in the slice header. > > * @nal_unit_type: specifies the coding type of the slice (B, P or I) > > @@ -356,7 +356,7 @@ struct v4l2_hevc_pred_weight_table { > > */ > > struct v4l2_ctrl_hevc_slice_params { > > __u32 bit_size; > > - __u32 data_bit_offset; > > + __u32 data_byte_offset; > > __u32 num_entry_point_offsets; > > /* ISO/IEC 23008-2, ITU-T Rec. H.265: NAL unit header */ > > __u8 nal_unit_type; > > -- > > 2.32.0 > > > > > > >
