119 lines
3.7 KiB
C
119 lines
3.7 KiB
C
/* SPDX-License-Identifier: LGPL-2.1+ */
|
|
/*
|
|
* Copyright 2016 Tom aan de Wiel
|
|
* Copyright 2018 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
|
|
*/
|
|
|
|
#ifndef CODEC_FWHT_H
|
|
#define CODEC_FWHT_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/bitops.h>
|
|
#include <asm/byteorder.h>
|
|
|
|
/*
|
|
* The compressed format consists of a fwht_cframe_hdr struct followed by the
|
|
* compressed frame data. The header contains the size of that data.
|
|
* Each Y, Cb and Cr plane is compressed separately. If the compressed
|
|
* size of each plane becomes larger than the uncompressed size, then
|
|
* that plane is stored uncompressed and the corresponding bit is set
|
|
* in the flags field of the header.
|
|
*
|
|
* Each compressed plane consists of macroblocks and each macroblock
|
|
* is run-length-encoded. Each macroblock starts with a 16 bit value.
|
|
* Bit 15 indicates if this is a P-coded macroblock (1) or not (0).
|
|
* P-coded macroblocks contain a delta against the previous frame.
|
|
*
|
|
* Bits 1-12 contain a number. If non-zero, then this same macroblock
|
|
* repeats that number of times. This results in a high degree of
|
|
* compression for generated images like colorbars.
|
|
*
|
|
* Following this macroblock header the MB coefficients are run-length
|
|
* encoded: the top 12 bits contain the coefficient, the bottom 4 bits
|
|
* tell how many times this coefficient occurs. The value 0xf indicates
|
|
* that the remainder of the macroblock should be filled with zeroes.
|
|
*
|
|
* All 16 and 32 bit values are stored in big-endian (network) order.
|
|
*
|
|
* Each fwht_cframe_hdr starts with an 8 byte magic header that is
|
|
* guaranteed not to occur in the compressed frame data. This header
|
|
* can be used to sync to the next frame.
|
|
*
|
|
* This codec uses the Fast Walsh Hadamard Transform. Tom aan de Wiel
|
|
* developed this as part of a university project, specifically for use
|
|
* with this driver. His project report can be found here:
|
|
*
|
|
* https://hverkuil.home.xs4all.nl/fwht.pdf
|
|
*/
|
|
|
|
/*
|
|
* This is a sequence of 8 bytes with the low 4 bits set to 0xf.
|
|
*
|
|
* This sequence cannot occur in the encoded data
|
|
*
|
|
* Note that these two magic values are symmetrical so endian issues here.
|
|
*/
|
|
#define FWHT_MAGIC1 0x4f4f4f4f
|
|
#define FWHT_MAGIC2 0xffffffff
|
|
|
|
/*
|
|
* A macro to calculate the needed padding in order to make sure
|
|
* both luma and chroma components resolutions are rounded up to
|
|
* a multiple of 8
|
|
*/
|
|
#define vic_round_dim(dim, div) (round_up((dim) / (div), 8) * (div))
|
|
|
|
struct fwht_cframe_hdr {
|
|
u32 magic1;
|
|
u32 magic2;
|
|
__be32 version;
|
|
__be32 width, height;
|
|
__be32 flags;
|
|
__be32 colorspace;
|
|
__be32 xfer_func;
|
|
__be32 ycbcr_enc;
|
|
__be32 quantization;
|
|
__be32 size;
|
|
};
|
|
|
|
struct fwht_cframe {
|
|
u16 i_frame_qp;
|
|
u16 p_frame_qp;
|
|
__be16 *rlc_data;
|
|
s16 coeffs[8 * 8];
|
|
s16 de_coeffs[8 * 8];
|
|
s16 de_fwht[8 * 8];
|
|
u32 size;
|
|
};
|
|
|
|
struct fwht_raw_frame {
|
|
unsigned int width_div;
|
|
unsigned int height_div;
|
|
unsigned int luma_alpha_step;
|
|
unsigned int chroma_step;
|
|
unsigned int components_num;
|
|
u8 *buf;
|
|
u8 *luma, *cb, *cr, *alpha;
|
|
};
|
|
|
|
#define FWHT_FRAME_PCODED BIT(0)
|
|
#define FWHT_FRAME_UNENCODED BIT(1)
|
|
#define FWHT_LUMA_UNENCODED BIT(2)
|
|
#define FWHT_CB_UNENCODED BIT(3)
|
|
#define FWHT_CR_UNENCODED BIT(4)
|
|
#define FWHT_ALPHA_UNENCODED BIT(5)
|
|
|
|
u32 fwht_encode_frame(struct fwht_raw_frame *frm,
|
|
struct fwht_raw_frame *ref_frm,
|
|
struct fwht_cframe *cf,
|
|
bool is_intra, bool next_is_intra,
|
|
unsigned int width, unsigned int height,
|
|
unsigned int stride, unsigned int chroma_stride);
|
|
bool fwht_decode_frame(struct fwht_cframe *cf, u32 hdr_flags,
|
|
unsigned int components_num, unsigned int width,
|
|
unsigned int height, const struct fwht_raw_frame *ref,
|
|
unsigned int ref_stride, unsigned int ref_chroma_stride,
|
|
struct fwht_raw_frame *dst, unsigned int dst_stride,
|
|
unsigned int dst_chroma_stride);
|
|
#endif
|