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1/* SPDX-License-Identifier: LGPL-2.1+ */2/*3 * Copyright 2016 Tom aan de Wiel4 * Copyright 2018 Cisco Systems, Inc. and/or its affiliates. All rights reserved.5 */6 7#ifndef CODEC_FWHT_H8#define CODEC_FWHT_H9 10#include <linux/types.h>11#include <linux/bitops.h>12#include <asm/byteorder.h>13 14/*15 * The compressed format consists of a fwht_cframe_hdr struct followed by the16 * compressed frame data. The header contains the size of that data.17 * Each Y, Cb and Cr plane is compressed separately. If the compressed18 * size of each plane becomes larger than the uncompressed size, then19 * that plane is stored uncompressed and the corresponding bit is set20 * in the flags field of the header.21 *22 * Each compressed plane consists of macroblocks and each macroblock23 * is run-length-encoded. Each macroblock starts with a 16 bit value.24 * Bit 15 indicates if this is a P-coded macroblock (1) or not (0).25 * P-coded macroblocks contain a delta against the previous frame.26 *27 * Bits 1-12 contain a number. If non-zero, then this same macroblock28 * repeats that number of times. This results in a high degree of29 * compression for generated images like colorbars.30 *31 * Following this macroblock header the MB coefficients are run-length32 * encoded: the top 12 bits contain the coefficient, the bottom 4 bits33 * tell how many times this coefficient occurs. The value 0xf indicates34 * that the remainder of the macroblock should be filled with zeroes.35 *36 * All 16 and 32 bit values are stored in big-endian (network) order.37 *38 * Each fwht_cframe_hdr starts with an 8 byte magic header that is39 * guaranteed not to occur in the compressed frame data. This header40 * can be used to sync to the next frame.41 *42 * This codec uses the Fast Walsh Hadamard Transform. Tom aan de Wiel43 * developed this as part of a university project, specifically for use44 * with this driver. His project report can be found here:45 *46 * https://hverkuil.home.xs4all.nl/fwht.pdf47 */48 49/*50 * This is a sequence of 8 bytes with the low 4 bits set to 0xf.51 *52 * This sequence cannot occur in the encoded data53 *54 * Note that these two magic values are symmetrical so endian issues here.55 */56#define FWHT_MAGIC1 0x4f4f4f4f57#define FWHT_MAGIC2 0xffffffff58 59/*60 * A macro to calculate the needed padding in order to make sure61 * both luma and chroma components resolutions are rounded up to62 * a multiple of 863 */64#define vic_round_dim(dim, div) (round_up((dim) / (div), 8) * (div))65 66struct fwht_cframe_hdr {67 u32 magic1;68 u32 magic2;69 __be32 version;70 __be32 width, height;71 __be32 flags;72 __be32 colorspace;73 __be32 xfer_func;74 __be32 ycbcr_enc;75 __be32 quantization;76 __be32 size;77};78 79struct fwht_cframe {80 u16 i_frame_qp;81 u16 p_frame_qp;82 __be16 *rlc_data;83 s16 coeffs[8 * 8];84 s16 de_coeffs[8 * 8];85 s16 de_fwht[8 * 8];86 u32 size;87};88 89struct fwht_raw_frame {90 unsigned int width_div;91 unsigned int height_div;92 unsigned int luma_alpha_step;93 unsigned int chroma_step;94 unsigned int components_num;95 u8 *buf;96 u8 *luma, *cb, *cr, *alpha;97};98 99#define FWHT_FRAME_PCODED BIT(0)100#define FWHT_FRAME_UNENCODED BIT(1)101#define FWHT_LUMA_UNENCODED BIT(2)102#define FWHT_CB_UNENCODED BIT(3)103#define FWHT_CR_UNENCODED BIT(4)104#define FWHT_ALPHA_UNENCODED BIT(5)105 106u32 fwht_encode_frame(struct fwht_raw_frame *frm,107 struct fwht_raw_frame *ref_frm,108 struct fwht_cframe *cf,109 bool is_intra, bool next_is_intra,110 unsigned int width, unsigned int height,111 unsigned int stride, unsigned int chroma_stride);112bool fwht_decode_frame(struct fwht_cframe *cf, u32 hdr_flags,113 unsigned int components_num, unsigned int width,114 unsigned int height, const struct fwht_raw_frame *ref,115 unsigned int ref_stride, unsigned int ref_chroma_stride,116 struct fwht_raw_frame *dst, unsigned int dst_stride,117 unsigned int dst_chroma_stride);118#endif119