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Re: [PATCH] PNG image reader
From: |
Marco Gerards |
Subject: |
Re: [PATCH] PNG image reader |
Date: |
Wed, 23 Jan 2008 11:36:58 +0100 |
User-agent: |
Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) |
Bean <address@hidden> writes:
Hi,
> remove longjmp, also add grub_png prefix to function names.
Thanks!
A changelog entry is missing, this is a single file. See the review
below for some comments.
--
Marco
> /*
> * GRUB -- GRand Unified Bootloader
> * Copyright (C) 2008 Free Software Foundation, Inc.
> *
> * GRUB is free software: you can redistribute it and/or modify
> * it under the terms of the GNU General Public License as published by
> * the Free Software Foundation, either version 3 of the License, or
> * (at your option) any later version.
> *
> * GRUB 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 General Public License for more details.
> *
> * You should have received a copy of the GNU General Public License
> * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
> */
>
> #include <grub/bitmap.h>
> #include <grub/types.h>
> #include <grub/normal.h>
> #include <grub/dl.h>
> #include <grub/mm.h>
> #include <grub/misc.h>
> #include <grub/arg.h>
> #include <grub/file.h>
>
> /* Uncomment following define to enable PNG debug. */
> //#define PNG_DEBUG
>
> #define PNG_COLOR_MASK_PALETTE 1
> #define PNG_COLOR_MASK_COLOR 2
> #define PNG_COLOR_MASK_ALPHA 4
>
> #define PNG_COLOR_TYPE_GRAY 0
> #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR |
> PNG_COLOR_MASK_PALETTE)
> #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
> #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR |
> PNG_COLOR_MASK_ALPHA)
> #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
> #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
> #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
>
> #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
>
> #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
>
> #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
> #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
>
> #define PNG_FILTER_VALUE_NONE 0
> #define PNG_FILTER_VALUE_SUB 1
> #define PNG_FILTER_VALUE_UP 2
> #define PNG_FILTER_VALUE_AVG 3
> #define PNG_FILTER_VALUE_PAETH 4
> #define PNG_FILTER_VALUE_LAST 5
>
> #define Z_DEFLATED 8
>
> #define Z_FLAG_DICT 32
>
> #define INFLATE_STORED 0
> #define INFLATE_FIXED 1
> #define INFLATE_DYNAMIC 2
>
> #define WSIZE 0x8000
>
> #define CHUNK_IHDR 0x49484452
> #define CHUNK_IDAT 0x49444154
> #define CHUNK_IEND 0x49454e44
>
> struct huff_table
> {
> int *values, *maxval, *offset;
> int num_values, max_length;
> };
>
> struct grub_png_data
> {
> grub_file_t file;
> struct grub_video_bitmap **bitmap;
>
> int bit_count, bit_save;
>
> int image_width, image_height;
>
> int bpp;
>
> int inside_idat, idat_remain;
>
> int code_values[286];
> int code_maxval[16];
> int code_offset[16];
>
> int dist_values[30];
> int dist_maxval[16];
> int dist_offset[16];
>
> struct huff_table code_table;
> struct huff_table dist_table;
>
> grub_uint8_t slide[WSIZE];
> int wp;
>
> grub_uint8_t *cur_rgb;
>
> int cur_colume, cur_filter, first_line;
> };
>
> static grub_uint32_t
> grub_png_get_dword (struct grub_png_data *data)
> {
> grub_uint32_t r;
>
> r = 0;
Why this?
> grub_file_read (data->file, (char *) &r, sizeof (grub_uint32_t));
>
> return grub_be_to_cpu32 (r);
> }
>
> static grub_uint8_t
> grub_png_get_byte (struct grub_png_data *data)
> {
> grub_uint8_t r;
>
> if ((data->inside_idat) && (data->idat_remain == 0))
> {
> grub_uint32_t len, type;
>
> do
> {
> grub_png_get_dword (data); /* skip crc checksum */
Please follow our style of commenting. Personally I prefer putting a
comment on a separate line.
> len = grub_png_get_dword (data);
> type = grub_png_get_dword (data);
> if (type != CHUNK_IDAT)
> {
> grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: unexpected end of data");
> return 0;
> }
> }
> while (len == 0);
> data->idat_remain = len;
> }
>
> r = 0;
...
> grub_file_read (data->file, (char *) &r, 1);
>
> if (data->inside_idat)
> data->idat_remain--;
>
> return r;
> }
>
> static int
> grub_png_get_bits (struct grub_png_data *data, int num)
> {
> int code, shift;
>
> if (data->bit_count == 0)
> {
> data->bit_save = grub_png_get_byte (data);
> data->bit_count = 8;
> }
>
> code = 0;
> shift = 0;
> while (grub_errno == 0)
> {
> int n;
>
> n = data->bit_count;
> if (n > num)
> n = num;
>
> code += (int) (data->bit_save & ((1 << n) - 1)) << shift;
> num -= n;
> if (!num)
> {
> data->bit_count -= n;
> data->bit_save >>= n;
> break;
> }
>
> shift += n;
>
> data->bit_save = grub_png_get_byte (data);
> data->bit_count = 8;
> }
>
> return code;
> }
>
> static grub_err_t
> grub_png_decode_image_header (struct grub_png_data *data)
> {
> int color_type;
>
> data->image_width = grub_png_get_dword (data);
> data->image_height = grub_png_get_dword (data);
>
> if ((!data->image_height) || (!data->image_width))
> return grub_error (GRUB_ERR_BAD_FILE_TYPE, "png: invalid image size");
>
> if (grub_png_get_byte (data) != 8)
> return grub_error (GRUB_ERR_BAD_FILE_TYPE, "png: bit depth must be 8");
>
> color_type = grub_png_get_byte (data);
> if (color_type == PNG_COLOR_TYPE_RGB)
> {
> if (grub_video_bitmap_create (data->bitmap, data->image_width,
> data->image_height,
> GRUB_VIDEO_BLIT_FORMAT_R8G8B8))
> return grub_errno;
I am not sure, is this indention correct?
> data->bpp = 3;
> }
> else if (color_type == PNG_COLOR_TYPE_RGBA)
> {
> if (grub_video_bitmap_create (data->bitmap, data->image_width,
> data->image_height,
> GRUB_VIDEO_BLIT_FORMAT_R8G8B8A8))
> return grub_errno;
> data->bpp = 4;
> }
> else
> return grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: color type not supported");
YUV isn't used here?
> data->cur_rgb = (*data->bitmap)->data;
> data->cur_colume = 0;
> data->first_line = 1;
>
> if (grub_png_get_byte (data) != PNG_COMPRESSION_TYPE_BASE)
> return grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: compression method not supported");
>
> if (grub_png_get_byte (data) != PNG_FILTER_TYPE_BASE)
> return grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: filter method not supported");
>
> if (grub_png_get_byte (data) != PNG_INTERLACE_NONE)
> return grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: interlace method not supported");
>
> grub_png_get_dword (data); /* skip crc checksum */
^^ comment
> return grub_errno;
> }
>
> static grub_uint8_t bitorder[] = { /* Order of the bit length code lengths
> */
> 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
> };
You can make this constant. Please fix the comment. Same for the
contants below.
> static int cplens[] = { /* Copy lengths for literal codes
> 257..285 */
> 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
> 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0
> };
>
> static grub_uint8_t cplext[] = { /* Extra bits for literal codes
> 257..285 */
> 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
> 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99
> }; /* 99==invalid */
>
> static int cpdist[] = { /* Copy offsets for distance codes
> 0..29 */
> 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
> 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
> 8193, 12289, 16385, 24577
> };
>
> static grub_uint8_t cpdext[] = { /* Extra bits for distance codes */
> 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
> 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
> 12, 12, 13, 13
> };
>
> static void
> grub_png_init_huff_table (struct huff_table *ht, int cur_maxlen,
> int *cur_values, int *cur_maxval, int *cur_offset)
> {
> ht->values = cur_values;
> ht->maxval = cur_maxval;
> ht->offset = cur_offset;
> ht->num_values = 0;
> ht->max_length = cur_maxlen;
> grub_memset (cur_maxval, 0, sizeof (int) * cur_maxlen);
> }
>
> static void
> grub_png_insert_huff_item (struct huff_table *ht, int code, int len)
> {
> int i, n;
>
> if (len == 0)
> return;
>
> if (len > ht->max_length)
> {
> grub_error (GRUB_ERR_BAD_FILE_TYPE, "png: invalid code length");
> return;
> }
>
> n = 0;
> for (i = len; i < ht->max_length; i++)
> n += ht->maxval[i];
>
> for (i = 0; i < n; i++)
> ht->values[ht->num_values - i] = ht->values[ht->num_values - i - 1];
>
> ht->values[ht->num_values - n] = code;
> ht->num_values++;
> ht->maxval[len - 1]++;
> }
>
> static void
> grub_png_build_huff_table (struct huff_table *ht)
> {
> int base, ofs, i;
>
> base = 0;
> ofs = 0;
> for (i = 0; i < ht->max_length; i++)
> {
> base += ht->maxval[i];
> ofs += ht->maxval[i];
>
> ht->maxval[i] = base;
> ht->offset[i] = ofs - base;
>
> base <<= 1;
> }
> }
>
> static int
> grub_png_get_huff_code (struct grub_png_data *data, struct huff_table *ht)
> {
> int code, i;
>
> code = 0;
> for (i = 0; i < ht->max_length; i++)
> {
> code = (code << 1) + grub_png_get_bits (data, 1);
> if (code < ht->maxval[i])
> return ht->values[code + ht->offset[i]];
> }
> return 0;
> }
Can this code above be shared with jpeg somehow?
> static grub_err_t
> grub_png_init_dynamic_block (struct grub_png_data *data)
> {
> int nl, nd, nb, i, prev;
> struct huff_table cl;
> int cl_values[sizeof (bitorder)];
> int cl_maxval[8];
> int cl_offset[8];
> grub_uint8_t lens[20];
>
> nl = 257 + grub_png_get_bits (data, 5);
> nd = 1 + grub_png_get_bits (data, 5);
> nb = 4 + grub_png_get_bits (data, 4);
> if ((nl > 286) || (nd > 30) || (nb > 19))
> return grub_error (GRUB_ERR_BAD_FILE_TYPE, "png: too much data");
Magic values...
> grub_png_init_huff_table (&cl, 8, cl_values, cl_maxval, cl_offset);
>
> for (i = 0; i < nb; i++)
> lens[bitorder[i]] = grub_png_get_bits (data, 3);
>
> for (; i < 19; i++)
> lens[bitorder[i]] = 0;
>
> for (i = 0; i < 19; i++)
> grub_png_insert_huff_item (&cl, i, lens[i]);
>
> grub_png_build_huff_table (&cl);
>
> grub_png_init_huff_table (&data->code_table, 16, data->code_values,
> data->code_maxval, data->code_offset);
> grub_png_init_huff_table (&data->dist_table, 16, data->dist_values,
> data->dist_maxval, data->dist_offset);
>
> prev = 0;
> for (i = 0; i < nl + nd; i++)
> {
> int n, code;
> struct huff_table *ht;
>
> if (grub_errno)
> return grub_errno;
>
> if (i < nl)
> {
> ht = &data->code_table;
> code = i;
> }
> else
> {
> ht = &data->dist_table;
> code = i - nl;
> }
>
> n = grub_png_get_huff_code (data, &cl);
> if (n < 16)
> {
> grub_png_insert_huff_item (ht, code, n);
> prev = n;
> }
> else if (n == 16)
> {
> int c;
>
> c = 3 + grub_png_get_bits (data, 2);
> while (c > 0)
> {
> grub_png_insert_huff_item (ht, code++, prev);
> i++;
> c--;
> }
> i--;
> }
> else if (n == 17)
> i += 3 + grub_png_get_bits (data, 3) - 1;
> else
> i += 11 + grub_png_get_bits (data, 7) - 1;
> }
>
> grub_png_build_huff_table (&data->code_table);
> grub_png_build_huff_table (&data->dist_table);
>
> return grub_errno;
> }
>
> static grub_err_t
> grub_png_output_byte (struct grub_png_data *data, grub_uint8_t n)
> {
> int row_bytes;
>
> if (data->cur_colume == 0)
> {
> if (n >= PNG_FILTER_VALUE_LAST)
> return grub_error (GRUB_ERR_BAD_FILE_TYPE, "invalid filter value");
>
> data->cur_filter = n;
> }
> else
> *(data->cur_rgb++) = n;
>
> data->cur_colume++;
> row_bytes = data->image_width * data->bpp;
> if (data->cur_colume == row_bytes + 1)
> {
> grub_uint8_t *blank_line = NULL;
> grub_uint8_t *cur = data->cur_rgb - row_bytes;
> grub_uint8_t *left = cur;
> grub_uint8_t *up;
>
> if (data->first_line)
> {
> blank_line = grub_malloc (row_bytes);
> if (grub_errno)
> return grub_errno;
>
> grub_memset (blank_line, 0, row_bytes);
> up = blank_line;
> }
> else
> up = cur - row_bytes;
>
> switch (data->cur_filter)
> {
> case PNG_FILTER_VALUE_SUB:
> {
> int i;
>
> cur += data->bpp;
> for (i = data->bpp; i < row_bytes; i++)
> *(cur++) += *(left++);
> break;
> }
> case PNG_FILTER_VALUE_UP:
> {
> int i;
>
> for (i = 0; i < row_bytes; i++)
> *(cur++) += *(up++);
>
> break;
> }
> case PNG_FILTER_VALUE_AVG:
> {
> int i;
>
> for (i = 0; i < data->bpp; i++)
> *(cur++) += *(up++) >> 1;
>
> for (; i < row_bytes; i++)
> *(cur++) += ((int) *(up++) + (int) *(left++)) >> 1;
>
> break;
> }
> case PNG_FILTER_VALUE_PAETH:
PAETH?
> {
> int i;
> grub_uint8_t *upper_left = up;
>
> for (i = 0; i < data->bpp; i++)
> *(cur++) += *(up++);
>
> for (; i < row_bytes; i++)
> {
> int a, b, c, pa, pb, pc, p;
>
> a = *(left++);
> b = *(up++);
> c = *(upper_left++);
>
> p = b - c;
> pc = a - c;
>
> pa = p < 0 ? -p : p;
> pb = pc < 0 ? -pc : pc;
> pc = (p + pc) < 0 ? -(p + pc) : p + pc;
>
> p = (pa <= pb && pa <= pc) ? a : (pb <= pc) ? b : c;
>
> *(cur++) += p;
> }
> }
> }
>
> if (blank_line)
> grub_free (blank_line);
>
> data->cur_colume = 0;
> data->first_line = 0;
> }
>
> return grub_errno;
> }
>
> static grub_err_t
> grub_png_read_dynamic_block (struct grub_png_data *data)
> {
> while (grub_errno == 0)
> {
> int n;
>
> n = grub_png_get_huff_code (data, &data->code_table);
> if (n < 256)
> {
> data->slide[data->wp] = n;
> grub_png_output_byte (data, n);
>
> data->wp++;
> if (data->wp >= WSIZE)
> data->wp = 0;
> }
> else if (n == 256)
> break;
> else
> {
> int len, dist, pos;
>
> n -= 257;
> len = cplens[n];
> if (cplext[n])
> len += grub_png_get_bits (data, cplext[n]);
>
> n = grub_png_get_huff_code (data, &data->dist_table);
> dist = cpdist[n];
> if (cpdext[n])
> dist += grub_png_get_bits (data, cpdext[n]);
>
> pos = data->wp - dist;
> if (pos < 0)
> pos += WSIZE;
>
> while (len > 0)
> {
> data->slide[data->wp] = data->slide[pos];
> grub_png_output_byte (data, data->slide[data->wp]);
>
> data->wp++;
> if (data->wp >= WSIZE)
> data->wp = 0;
>
> pos++;
> if (pos >= WSIZE)
> pos = 0;
>
> len--;
> }
> }
> }
>
> return grub_errno;
> }
>
> static grub_err_t
> grub_png_decode_image_data (struct grub_png_data *data)
> {
> grub_uint8_t cmf, flg;
> int final;
>
> cmf = grub_png_get_byte (data);
> flg = grub_png_get_byte (data);
>
> if ((cmf & 0xF) != Z_DEFLATED)
> return grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: only support deflate compression method");
>
> if (flg & Z_FLAG_DICT)
> return grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: dictionary not supported");
>
> do
> {
> int block_type;
>
> final = grub_png_get_bits (data, 1);
> block_type = grub_png_get_bits (data, 2);
>
> switch (block_type)
> {
> case INFLATE_STORED:
> {
> grub_uint16_t i, len;
>
> data->bit_count = 0;
> len = grub_png_get_byte (data);
> len += ((grub_uint16_t) grub_png_get_byte (data)) << 8;
>
> grub_png_get_byte (data); /* skip NLEN field */
> grub_png_get_byte (data);
>
> for (i = 0; i < len; i++)
> grub_png_output_byte (data, grub_png_get_byte (data));
>
> break;
> }
>
> case INFLATE_FIXED:
> return grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: block type fixed not supported");
>
> case INFLATE_DYNAMIC:
> grub_png_init_dynamic_block (data);
> grub_png_read_dynamic_block (data);
> break;
>
> default:
> return grub_error (GRUB_ERR_BAD_FILE_TYPE,
> "png: unknown block type");
> }
> }
> while ((!final) && (grub_errno == 0));
>
> grub_png_get_dword (data); /* skip adler checksum */
> grub_png_get_dword (data); /* skip crc checksum */
adler?
Please fix the comments.
> return grub_errno;
> }
>
> static grub_uint8_t png_magic[8] =
> { 0x89, 0x50, 0x4e, 0x47, 0xd, 0xa, 0x1a, 0x0a };
Constant?
> static grub_err_t
> grub_png_decode_png (struct grub_png_data *data)
> {
> grub_uint8_t magic[8];
>
> if (grub_file_read (data->file, (char *) &magic[0], 8) != 8)
> return grub_errno;
>
> if (grub_memcmp (magic, png_magic, sizeof (png_magic)))
> return grub_error (GRUB_ERR_BAD_FILE_TYPE, "png: not a png file");
>
> while (grub_errno == 0)
> {
> grub_uint32_t len, type;
>
> len = grub_png_get_dword (data);
> type = grub_png_get_dword (data);
>
> switch (type)
> {
> case CHUNK_IHDR:
> grub_png_decode_image_header (data);
> break;
>
> case CHUNK_IDAT:
> data->inside_idat = 1;
> data->idat_remain = len;
> data->bit_count = 0;
>
> grub_png_decode_image_data (data);
>
> data->inside_idat = 0;
> break;
>
> case CHUNK_IEND:
> return grub_errno;
>
> default:
> grub_file_seek (data->file, data->file->offset + len + 4);
> }
> }
>
> return grub_errno;
> }
>
> static grub_err_t
> grub_video_reader_png (struct grub_video_bitmap **bitmap,
> const char *filename)
> {
> grub_file_t file;
> struct grub_png_data *data;
>
> file = grub_file_open (filename);
> if (!file)
> return grub_errno;
>
> data = grub_malloc (sizeof (*data));
> if (data != NULL)
> {
> grub_memset (data, 0, sizeof (*data));
> data->file = file;
> data->bitmap = bitmap;
>
> grub_png_decode_png (data);
>
> grub_free (data);
> }
>
> if (grub_errno != GRUB_ERR_NONE)
> {
> grub_video_bitmap_destroy (*bitmap);
> *bitmap = 0;
> }
>
> grub_file_close (file);
> return grub_errno;
> }
>
> #if defined(PNG_DEBUG)
> static grub_err_t
> grub_cmd_pngtest (struct grub_arg_list *state __attribute__ ((unused)),
> int argc, char **args)
> {
> struct grub_video_bitmap *bitmap = 0;
>
> if (argc != 1)
> return grub_error (GRUB_ERR_BAD_ARGUMENT, "file name required");
>
> grub_video_reader_png (&bitmap, args[0]);
> if (grub_errno != GRUB_ERR_NONE)
> return grub_errno;
>
> grub_video_bitmap_destroy (bitmap);
>
> return GRUB_ERR_NONE;
> }
> #endif
>
> static struct grub_video_bitmap_reader png_reader = {
> .extension = ".png",
> .reader = grub_video_reader_png,
> .next = 0
> };
>
> GRUB_MOD_INIT (video_reader_png)
> {
> grub_video_bitmap_reader_register (&png_reader);
> #if defined(PNG_DEBUG)
> grub_register_command ("pngtest", grub_cmd_pngtest,
> GRUB_COMMAND_FLAG_BOTH, "pngtest FILE",
> "Tests loading of PNG bitmap.", 0);
> #endif
> }
>
> GRUB_MOD_FINI (video_reader_png)
> {
> #if defined(PNG_DEBUG)
> grub_unregister_command ("pngtest");
> #endif
> grub_video_bitmap_reader_unregister (&png_reader);
> }
- [PATCH] PNG image reader, Bean, 2008/01/11
- Re: [PATCH] PNG image reader, Bean, 2008/01/12
- Re: [PATCH] PNG image reader, Bean, 2008/01/14
- Re: [PATCH] PNG image reader,
Marco Gerards <=
- Re: [PATCH] PNG image reader, Bean, 2008/01/23
- Re: [PATCH] PNG image reader, Marco Gerards, 2008/01/24
- Re: [PATCH] PNG image reader, Bean, 2008/01/24
- Re: [PATCH] PNG image reader, Marco Gerards, 2008/01/24
- Re: [PATCH] PNG image reader, Bean, 2008/01/24
- Re: [PATCH] PNG image reader, Marco Gerards, 2008/01/25
- Re: [PATCH] PNG image reader, Bean, 2008/01/26
- Re: [PATCH] PNG image reader, Marco Gerards, 2008/01/29
- Re: [PATCH] PNG image reader, Bean, 2008/01/29