[FFmpeg-devel,1/2] avcodec/jpeg2000dec: Move decoder structs to header files

From: caleb <etemesicaleb@gmail.com>

This should pave way for HTJ2K decoding

---
 libavcodec/jpeg2000dec.c |  96 +----------------------------
 libavcodec/jpeg2000dec.h | 126 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 127 insertions(+), 95 deletions(-)
 create mode 100644 libavcodec/jpeg2000dec.h

etemesicaleb@gmail.com:
> From: caleb <etemesicaleb@gmail.com>
> 
> This should pave way for HTJ2K decoding
> 
> ---
>  libavcodec/jpeg2000dec.c |  96 +----------------------------
>  libavcodec/jpeg2000dec.h | 126 +++++++++++++++++++++++++++++++++++++++
>  2 files changed, 127 insertions(+), 95 deletions(-)
>  create mode 100644 libavcodec/jpeg2000dec.h
> 
> diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
> index c2b81ec103..7fc09cb558 100644
> --- a/libavcodec/jpeg2000dec.c
> +++ b/libavcodec/jpeg2000dec.c
> @@ -42,101 +42,7 @@
>  #include "jpeg2000.h"
>  #include "jpeg2000dsp.h"
>  #include "profiles.h"
> -
> -#define JP2_SIG_TYPE    0x6A502020
> -#define JP2_SIG_VALUE   0x0D0A870A
> -#define JP2_CODESTREAM  0x6A703263
> -#define JP2_HEADER      0x6A703268
> -
> -#define HAD_COC 0x01
> -#define HAD_QCC 0x02
> -
> -#define MAX_POCS 32
> -
> -typedef struct Jpeg2000POCEntry {
> -    uint16_t LYEpoc;
> -    uint16_t CSpoc;
> -    uint16_t CEpoc;
> -    uint8_t RSpoc;
> -    uint8_t REpoc;
> -    uint8_t Ppoc;
> -} Jpeg2000POCEntry;
> -
> -typedef struct Jpeg2000POC {
> -    Jpeg2000POCEntry poc[MAX_POCS];
> -    int nb_poc;
> -    int is_default;
> -} Jpeg2000POC;
> -
> -typedef struct Jpeg2000TilePart {
> -    uint8_t tile_index;                 // Tile index who refers the tile-part
> -    const uint8_t *tp_end;
> -    GetByteContext header_tpg;          // bit stream of header if PPM header is used
> -    GetByteContext tpg;                 // bit stream in tile-part
> -} Jpeg2000TilePart;
> -
> -/* RMK: For JPEG2000 DCINEMA 3 tile-parts in a tile
> - * one per component, so tile_part elements have a size of 3 */
> -typedef struct Jpeg2000Tile {
> -    Jpeg2000Component   *comp;
> -    uint8_t             properties[4];
> -    Jpeg2000CodingStyle codsty[4];
> -    Jpeg2000QuantStyle  qntsty[4];
> -    Jpeg2000POC         poc;
> -    Jpeg2000TilePart    tile_part[32];
> -    uint8_t             has_ppt;                // whether this tile has a ppt marker
> -    uint8_t             *packed_headers;        // contains packed headers. Used only along with PPT marker
> -    int                 packed_headers_size;    // size in bytes of the packed headers
> -    GetByteContext      packed_headers_stream;  // byte context corresponding to packed headers
> -    uint16_t tp_idx;                    // Tile-part index
> -    int coord[2][2];                    // border coordinates {{x0, x1}, {y0, y1}}
> -} Jpeg2000Tile;
> -
> -typedef struct Jpeg2000DecoderContext {
> -    AVClass         *class;
> -    AVCodecContext  *avctx;
> -    GetByteContext  g;
> -
> -    int             width, height;
> -    int             image_offset_x, image_offset_y;
> -    int             tile_offset_x, tile_offset_y;
> -    uint8_t         cbps[4];    // bits per sample in particular components
> -    uint8_t         sgnd[4];    // if a component is signed
> -    uint8_t         properties[4];
> -
> -    uint8_t         has_ppm;
> -    uint8_t         *packed_headers; // contains packed headers. Used only along with PPM marker
> -    int             packed_headers_size;
> -    GetByteContext  packed_headers_stream;
> -    uint8_t         in_tile_headers;
> -
> -    int             cdx[4], cdy[4];
> -    int             precision;
> -    int             ncomponents;
> -    int             colour_space;
> -    uint32_t        palette[256];
> -    int8_t          pal8;
> -    int             cdef[4];
> -    int             tile_width, tile_height;
> -    unsigned        numXtiles, numYtiles;
> -    int             maxtilelen;
> -    AVRational      sar;
> -
> -    Jpeg2000CodingStyle codsty[4];
> -    Jpeg2000QuantStyle  qntsty[4];
> -    Jpeg2000POC         poc;
> -    uint8_t             roi_shift[4];
> -
> -    int             bit_index;
> -
> -    int             curtileno;
> -
> -    Jpeg2000Tile    *tile;
> -    Jpeg2000DSPContext dsp;
> -
> -    /*options parameters*/
> -    int             reduction_factor;
> -} Jpeg2000DecoderContext;
> +#include "jpeg2000dec.h"
>  
>  /* get_bits functions for JPEG2000 packet bitstream
>   * It is a get_bit function with a bit-stuffing routine. If the value of the
> diff --git a/libavcodec/jpeg2000dec.h b/libavcodec/jpeg2000dec.h
> new file mode 100644
> index 0000000000..b6410c1432
> --- /dev/null
> +++ b/libavcodec/jpeg2000dec.h
> @@ -0,0 +1,126 @@
> +/*
> + * JPEG 2000 image decoder
> + * Copyright (c) 2007 Kamil Nowosad
> + * Copyright (c) 2013 Nicolas Bertrand <nicoinattendu@gmail.com>
> + * Copyright (c) 2022 Caleb Etemesi <etemesicaleb@gmail.com>
> + *
> + * This file is part of FFmpeg.
> + *
> + * FFmpeg is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * FFmpeg is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with FFmpeg; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#ifndef AVCODEC_JPEG2000DEC_H
> +#define AVCODEC_JPEG2000DEC_H
> +
> +#include "bytestream.h"
> +#include "jpeg2000.h"
> +#include "jpeg2000dsp.h"
> +
> +#define JP2_SIG_TYPE    0x6A502020
> +#define JP2_SIG_VALUE   0x0D0A870A
> +#define JP2_CODESTREAM  0x6A703263
> +#define JP2_HEADER      0x6A703268
> +

This stuff seems to be only used in jpeg2000dec.c, so it can stay there.
Given that this is format-specific (and not specific to our
decoder-implementation, a better place for this would be jpeg2000.h if
it were moved out of jpeg2000dec.c).

> +#define HAD_COC 0x01
> +#define HAD_QCC 0x02
> +

These two should not be in this header, they are only used in
jpeg2000dec.c and seems to be decoder-only and not format specific at all.

> +#define MAX_POCS 32

If this is moved to a header, it should have a proper prefix in order to
avoid future clashes.

> +
> +typedef struct Jpeg2000POCEntry {
> +    uint16_t LYEpoc;
> +    uint16_t CSpoc;
> +    uint16_t CEpoc;
> +    uint8_t RSpoc;
> +    uint8_t REpoc;
> +    uint8_t Ppoc;
> +} Jpeg2000POCEntry;
> +
> +typedef struct Jpeg2000POC {
> +    Jpeg2000POCEntry poc[MAX_POCS];
> +    int nb_poc;
> +    int is_default;
> +} Jpeg2000POC;
> +
> +typedef struct Jpeg2000TilePart {
> +    uint8_t tile_index;                 // Tile index who refers the tile-part
> +    const uint8_t *tp_end;
> +    GetByteContext header_tpg;          // bit stream of header if PPM header is used
> +    GetByteContext tpg;                 // bit stream in tile-part
> +} Jpeg2000TilePart;
> +
> +/* RMK: For JPEG2000 DCINEMA 3 tile-parts in a tile
> + * one per component, so tile_part elements have a size of 3 */
> +typedef struct Jpeg2000Tile {
> +    Jpeg2000Component   *comp;
> +    uint8_t             properties[4];
> +    Jpeg2000CodingStyle codsty[4];
> +    Jpeg2000QuantStyle  qntsty[4];
> +    Jpeg2000POC         poc;
> +    Jpeg2000TilePart    tile_part[32];
> +    uint8_t             has_ppt;                // whether this tile has a ppt marker
> +    uint8_t             *packed_headers;        // contains packed headers. Used only along with PPT marker
> +    int                 packed_headers_size;    // size in bytes of the packed headers
> +    GetByteContext      packed_headers_stream;  // byte context corresponding to packed headers
> +    uint16_t tp_idx;                    // Tile-part index
> +    int coord[2][2];                    // border coordinates {{x0, x1}, {y0, y1}}
> +} Jpeg2000Tile;

Seems like there is no reason to put Jpeg2000TilePart and Jpeg2000Tile
into this header, as it is only used in jpeg2000dec.c (the usage below
only uses a Jpeg2000Tile* and can therefore use an incomplete type).

> +
> +typedef struct Jpeg2000DecoderContext {
> +    AVClass         *class;

const AVClass* would be better.

> +    AVCodecContext  *avctx;
> +    GetByteContext  g;
> +
> +    int             width, height;
> +    int             image_offset_x, image_offset_y;
> +    int             tile_offset_x, tile_offset_y;
> +    uint8_t         cbps[4];    // bits per sample in particular components
> +    uint8_t         sgnd[4];    // if a component is signed
> +    uint8_t         properties[4];
> +
> +    uint8_t         has_ppm;
> +    uint8_t         *packed_headers; // contains packed headers. Used only along with PPM marker
> +    int             packed_headers_size;
> +    GetByteContext  packed_headers_stream;
> +    uint8_t         in_tile_headers;
> +
> +    int             cdx[4], cdy[4];
> +    int             precision;
> +    int             ncomponents;
> +    int             colour_space;
> +    uint32_t        palette[256];
> +    int8_t          pal8;
> +    int             cdef[4];
> +    int             tile_width, tile_height;
> +    unsigned        numXtiles, numYtiles;
> +    int             maxtilelen;
> +    AVRational      sar;
> +
> +    Jpeg2000CodingStyle codsty[4];
> +    Jpeg2000QuantStyle  qntsty[4];
> +    Jpeg2000POC         poc;
> +    uint8_t             roi_shift[4];
> +
> +    int             bit_index;
> +
> +    int             curtileno;
> +
> +    Jpeg2000Tile    *tile;
> +    Jpeg2000DSPContext dsp;
> +
> +    /*options parameters*/
> +    int             reduction_factor;
> +} Jpeg2000DecoderContext;
> +
> +#endif //AVCODEC_JPEG2000DEC_H