drivers/media/platform/vicodec/vicodec-codec.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright 2016 Tom aan de Wiel
   4  * Copyright 2018 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
   5  */
   6
   7 #ifndef VICODEC_RLC_H
   8 #define VICODEC_RLC_H
   9
  10 #include <linux/types.h>
  11 #include <linux/bitops.h>
  12 #include <asm/byteorder.h>
  13
  14 /*
  15  * The compressed format consists of a cframe_hdr struct followed by the
  16  * compressed frame data. The header contains the size of that data.
  17  * Each Y, Cb and Cr plane is compressed separately. If the compressed
  18  * size of each plane becomes larger than the uncompressed size, then
  19  * that plane is stored uncompressed and the corresponding bit is set
  20  * in the flags field of the header.
  21  *
  22  * Each compressed plane consists of macroblocks and each macroblock
  23  * 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 macroblock
  28  * repeats that number of times. This results in a high degree of
  29  * compression for generated images like colorbars.
  30  *
  31  * Following this macroblock header the MB coefficients are run-length
  32  * encoded: the top 12 bits contain the coefficient, the bottom 4 bits
  33  * tell how many times this coefficient occurs. The value 0xf indicates
  34  * 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 cframe_hdr starts with an 8 byte magic header that is
  39  * guaranteed not to occur in the compressed frame data. This header
  40  * can be used to sync to the next frame.
  41  *
  42  * This codec uses the Fast Walsh Hadamard Transform. Tom aan de Wiel
  43  * developed this as part of a university project, specifically for use
  44  * with this driver. His project report can be found here:
  45  *
  46  * https://hverkuil.home.xs4all.nl/fwht.pdf
  47  */
  48
  49 /*
  50  * Note: bit 0 of the header must always be 0. Otherwise it cannot
  51  * be guaranteed that the magic 8 byte sequence (see below) can
  52  * never occur in the rlc output.
  53  */
  54 #define PFRAME_BIT (1 << 15)
  55 #define DUPS_MASK 0x1ffe
  56
  57 /*
  58  * This is a sequence of 8 bytes with the low 4 bits set to 0xf.
  59  *
  60  * This sequence cannot occur in the encoded data
  61  */
  62 #define VICODEC_MAGIC1 0x4f4f4f4f
  63 #define VICODEC_MAGIC2 0xffffffff
  64
  65 #define VICODEC_VERSION 1
  66
  67 #define VICODEC_MAX_WIDTH 3840
  68 #define VICODEC_MAX_HEIGHT 2160
  69 #define VICODEC_MIN_WIDTH 640
  70 #define VICODEC_MIN_HEIGHT 480
  71
  72 #define PBLOCK 0
  73 #define IBLOCK 1
  74
  75 /* Set if this is an interlaced format */
  76 #define VICODEC_FL_IS_INTERLACED        BIT(0)
  77 /* Set if this is a bottom-first (NTSC) interlaced format */
  78 #define VICODEC_FL_IS_BOTTOM_FIRST      BIT(1)
  79 /* Set if each 'frame' contains just one field */
  80 #define VICODEC_FL_IS_ALTERNATE         BIT(2)
  81 /*
  82  * If VICODEC_FL_IS_ALTERNATE was set, then this is set if this
  83  * 'frame' is the bottom field, else it is the top field.
  84  */
  85 #define VICODEC_FL_IS_BOTTOM_FIELD      BIT(3)
  86 /* Set if this frame is uncompressed */
  87 #define VICODEC_FL_LUMA_IS_UNCOMPRESSED BIT(4)
  88 #define VICODEC_FL_CB_IS_UNCOMPRESSED   BIT(5)
  89 #define VICODEC_FL_CR_IS_UNCOMPRESSED   BIT(6)
  90
  91 struct cframe_hdr {
  92         u32 magic1;
  93         u32 magic2;
  94         __be32 version;
  95         __be32 width, height;
  96         __be32 flags;
  97         __be32 colorspace;
  98         __be32 xfer_func;
  99         __be32 ycbcr_enc;
 100         __be32 quantization;
 101         __be32 size;
 102 };
 103
 104 struct cframe {
 105         unsigned int width, height;
 106         __be16 *rlc_data;
 107         s16 coeffs[8 * 8];
 108         s16 de_coeffs[8 * 8];
 109         s16 de_fwht[8 * 8];
 110         u32 size;
 111 };
 112
 113 struct raw_frame {
 114         unsigned int width, height;
 115         unsigned int chroma_step;
 116         u8 *luma, *cb, *cr;
 117 };
 118
 119 #define FRAME_PCODED    BIT(0)
 120 #define FRAME_UNENCODED BIT(1)
 121 #define LUMA_UNENCODED  BIT(2)
 122 #define CB_UNENCODED    BIT(3)
 123 #define CR_UNENCODED    BIT(4)
 124
 125 u32 encode_frame(struct raw_frame *frm, struct raw_frame *ref_frm,
 126                  struct cframe *cf, bool is_intra, bool next_is_intra);
 127 void decode_frame(struct cframe *cf, struct raw_frame *ref, u32 hdr_flags);
 128
 129 #endif