diff options
| -rw-r--r-- | apps/plugins/jpeg.c | 233 |
1 files changed, 222 insertions, 11 deletions
diff --git a/apps/plugins/jpeg.c b/apps/plugins/jpeg.c index e24c048ae8..408f5d1ea1 100644 --- a/apps/plugins/jpeg.c +++ b/apps/plugins/jpeg.c @@ -669,7 +669,7 @@ struct jpeg int x_phys, y_phys; /* physical size, block aligned */ int x_mbl; /* x dimension of MBL */ int y_mbl; /* y dimension of MBL */ - int blocks; /* blocks per MBL */ + int blocks; /* blocks per MB */ int restart_interval; /* number of MCUs between RSTm markers */ int store_pos[4]; /* for Y block ordering */ @@ -688,6 +688,8 @@ struct jpeg int mcu_membership[6]; /* info per block */ int tab_membership[6]; + int subsample_x[3]; /* info per component */ + int subsample_y[3]; }; @@ -1126,14 +1128,20 @@ void build_lut(struct jpeg* p_jpeg) p_jpeg->x_phys = p_jpeg->x_mbl * 16; p_jpeg->y_mbl = (p_jpeg->y_size+7) / 8; p_jpeg->y_phys = p_jpeg->y_mbl * 8; - p_jpeg->mcu_membership[0] = 0; /* Y1=Y2=0, U=2, V=3 */ + p_jpeg->mcu_membership[0] = 0; /* Y1=Y2=0, U=1, V=2 */ p_jpeg->mcu_membership[1] = 0; - p_jpeg->mcu_membership[2] = 2; - p_jpeg->mcu_membership[3] = 3; + p_jpeg->mcu_membership[2] = 1; + p_jpeg->mcu_membership[3] = 2; p_jpeg->tab_membership[0] = 0; /* DC, DC, AC, AC */ p_jpeg->tab_membership[1] = 0; p_jpeg->tab_membership[2] = 1; p_jpeg->tab_membership[3] = 1; + p_jpeg->subsample_x[0] = 1; + p_jpeg->subsample_x[1] = 2; + p_jpeg->subsample_x[2] = 2; + p_jpeg->subsample_y[0] = 1; + p_jpeg->subsample_y[1] = 1; + p_jpeg->subsample_y[2] = 1; } if (p_jpeg->frameheader[0].horizontal_sampling == 1 && p_jpeg->frameheader[0].vertical_sampling == 2) @@ -1145,14 +1153,20 @@ void build_lut(struct jpeg* p_jpeg) p_jpeg->x_phys = p_jpeg->x_mbl * 8; p_jpeg->y_mbl = (p_jpeg->y_size+15) / 16; p_jpeg->y_phys = p_jpeg->y_mbl * 16; - p_jpeg->mcu_membership[0] = 0; /* Y1=Y2=0, U=2, V=3 */ + p_jpeg->mcu_membership[0] = 0; /* Y1=Y2=0, U=1, V=2 */ p_jpeg->mcu_membership[1] = 0; - p_jpeg->mcu_membership[2] = 2; - p_jpeg->mcu_membership[3] = 3; + p_jpeg->mcu_membership[2] = 1; + p_jpeg->mcu_membership[3] = 2; p_jpeg->tab_membership[0] = 0; /* DC, DC, AC, AC */ p_jpeg->tab_membership[1] = 0; p_jpeg->tab_membership[2] = 1; p_jpeg->tab_membership[3] = 1; + p_jpeg->subsample_x[0] = 1; + p_jpeg->subsample_x[1] = 1; + p_jpeg->subsample_x[2] = 1; + p_jpeg->subsample_y[0] = 1; + p_jpeg->subsample_y[1] = 2; + p_jpeg->subsample_y[2] = 2; } else if (p_jpeg->frameheader[0].horizontal_sampling == 2 && p_jpeg->frameheader[0].vertical_sampling == 2) @@ -1166,14 +1180,20 @@ void build_lut(struct jpeg* p_jpeg) p_jpeg->mcu_membership[1] = 0; p_jpeg->mcu_membership[2] = 0; p_jpeg->mcu_membership[3] = 0; - p_jpeg->mcu_membership[4] = 2; - p_jpeg->mcu_membership[5] = 3; + p_jpeg->mcu_membership[4] = 1; + p_jpeg->mcu_membership[5] = 2; p_jpeg->tab_membership[0] = 0; p_jpeg->tab_membership[1] = 0; p_jpeg->tab_membership[2] = 0; p_jpeg->tab_membership[3] = 0; p_jpeg->tab_membership[4] = 1; p_jpeg->tab_membership[5] = 1; + p_jpeg->subsample_x[0] = 1; + p_jpeg->subsample_x[1] = 2; + p_jpeg->subsample_x[2] = 2; + p_jpeg->subsample_y[0] = 1; + p_jpeg->subsample_y[1] = 2; + p_jpeg->subsample_y[2] = 2; } else if (p_jpeg->frameheader[0].horizontal_sampling == 1 && p_jpeg->frameheader[0].vertical_sampling == 1) @@ -1184,11 +1204,21 @@ void build_lut(struct jpeg* p_jpeg) p_jpeg->y_mbl = (p_jpeg->y_size+7) / 8; p_jpeg->y_phys = p_jpeg->y_mbl * 8; p_jpeg->mcu_membership[0] = 0; - p_jpeg->mcu_membership[1] = 2; - p_jpeg->mcu_membership[2] = 3; + p_jpeg->mcu_membership[1] = 1; + p_jpeg->mcu_membership[2] = 2; p_jpeg->tab_membership[0] = 0; p_jpeg->tab_membership[1] = 1; p_jpeg->tab_membership[2] = 1; + p_jpeg->subsample_x[0] = 1; + p_jpeg->subsample_x[1] = 1; + p_jpeg->subsample_x[2] = 1; + p_jpeg->subsample_y[0] = 1; + p_jpeg->subsample_y[1] = 1; + p_jpeg->subsample_y[2] = 1; + } + else + { + // error } } @@ -1523,6 +1553,187 @@ int jpeg_decode(struct jpeg* p_jpeg, unsigned char* p_pixel, int downscale, } +#ifdef HAVE_LCD_COLOR + +/* JPEG decoder variant for YUV decoding, into 3 different planes */ +/* Note: it keeps the original color subsampling, even if resized. */ +int jpeg_decode_color(struct jpeg* p_jpeg, unsigned char* p_pixel[3], + int downscale, void (*pf_progress)(int current, int total)) +{ + struct bitstream bs; /* bitstream "object" */ + static int block[64]; /* decoded DCT coefficients */ + + int width, height; + int skip_line[3]; /* bytes from one line to the next (skip_line) */ + int skip_strip[3], skip_mcu[3]; /* bytes to next DCT row / column */ + + int i, x, y; /* loop counter */ + + unsigned char* p_line[3] = {p_pixel[0], p_pixel[1], p_pixel[2]}; + unsigned char* p_byte[3]; /* bitmap pointer */ + + void (*pf_idct)(unsigned char*, int*, int*, int); /* selected IDCT */ + int k_need; /* AC coefficients needed up to here */ + int zero_need; /* init the block with this many zeros */ + + int last_dc_val[3] = {0, 0, 0}; // or 128 for chroma? + int store_offs[4]; /* memory offsets: order of Y11 Y12 Y21 Y22 U V */ + int restart = p_jpeg->restart_interval; /* MCUs until restart marker */ + + /* pick the IDCT we want, determine how to work with coefs */ + if (downscale == 1) + { + pf_idct = idct8x8; + k_need = 64; /* all */ + zero_need = 63; /* all */ + } + else if (downscale == 2) + { + pf_idct = idct4x4; + k_need = 25; /* this far in zig-zag to cover 4*4 */ + zero_need = 27; /* clear this far in linear order */ + } + else if (downscale == 4) + { + pf_idct = idct2x2; + k_need = 5; /* this far in zig-zag to cover 2*2 */ + zero_need = 9; /* clear this far in linear order */ + } + else if (downscale == 8) + { + pf_idct = idct1x1; + k_need = 0; /* no AC, not needed */ + zero_need = 0; /* no AC, not needed */ + } + else return -1; /* not supported */ + + /* init bitstream, fake a restart to make it start */ + bs.next_input_byte = p_jpeg->p_entropy_data; + bs.bits_left = 0; + bs.input_end = p_jpeg->p_entropy_end; + + width = p_jpeg->x_phys / downscale; + height = p_jpeg->y_phys / downscale; + for (i=0; i<3; i++) /* calculate some strides */ + { + skip_line[i] = width / p_jpeg->subsample_x[i]; + skip_strip[i] = skip_line[i] + * (height / p_jpeg->y_mbl) / p_jpeg->subsample_y[i]; + skip_mcu[i] = width/p_jpeg->x_mbl / p_jpeg->subsample_x[i]; + } + + /* prepare offsets about where to store the different blocks */ + store_offs[p_jpeg->store_pos[0]] = 0; + store_offs[p_jpeg->store_pos[1]] = 8 / downscale; /* to the right */ + store_offs[p_jpeg->store_pos[2]] = width * 8 / downscale; /* below */ + store_offs[p_jpeg->store_pos[3]] = store_offs[1] + store_offs[2]; /* r+b */ + + for(y=0; y<p_jpeg->y_mbl && bs.next_input_byte <= bs.input_end; y++) + { + for (i=0; i<3; i++) // scan line init + { + p_byte[i] = p_line[i]; + p_line[i] += skip_strip[i]; + } + for (x=0; x<p_jpeg->x_mbl; x++) + { + int blkn; + + /* Outer loop handles each block in the MCU */ + for (blkn = 0; blkn < p_jpeg->blocks; blkn++) + { /* Decode a single block's worth of coefficients */ + int k = 1; /* coefficient index */ + int s, r; /* huffman values */ + int ci = p_jpeg->mcu_membership[blkn]; /* component index */ + int ti = p_jpeg->tab_membership[blkn]; /* table index */ + struct derived_tbl* dctbl = &p_jpeg->dc_derived_tbls[ti]; + struct derived_tbl* actbl = &p_jpeg->ac_derived_tbls[ti]; + + /* Section F.2.2.1: decode the DC coefficient difference */ + s = huff_decode_dc(&bs, dctbl); + + last_dc_val[ci] += s; + block[0] = last_dc_val[ci]; /* output it (assumes zag[0] = 0) */ + + /* coefficient buffer must be cleared */ + MEMSET(block+1, 0, zero_need*sizeof(block[0])); + + /* Section F.2.2.2: decode the AC coefficients */ + for (; k < k_need; k++) + { + s = huff_decode_ac(&bs, actbl); + r = s >> 4; + s &= 15; + + if (s) + { + k += r; + check_bit_buffer(&bs, s); + r = get_bits(&bs, s); + block[zag[k]] = HUFF_EXTEND(r, s); + } + else + { + if (r != 15) + { + k = 64; + break; + } + k += r; + } + } /* for k */ + /* In this path we just discard the values */ + for (; k < 64; k++) + { + s = huff_decode_ac(&bs, actbl); + r = s >> 4; + s &= 15; + + if (s) + { + k += r; + check_bit_buffer(&bs, s); + drop_bits(&bs, s); + } + else + { + if (r != 15) + break; + k += r; + } + } /* for k */ + + if (ci == 0) + { /* Y component needs to bother about block store */ + pf_idct(p_byte[0]+store_offs[blkn], block, + p_jpeg->qt_idct[ti], skip_line[0]); + } + else + { /* chroma */ + pf_idct(p_byte[ci], block, p_jpeg->qt_idct[ti], + skip_line[ci]); + } + } /* for blkn */ + p_byte[0] += skip_mcu[0]; // unrolled for (i=0; i<3; i++) loop + p_byte[1] += skip_mcu[1]; + p_byte[2] += skip_mcu[2]; + if (p_jpeg->restart_interval && --restart == 0) + { /* if a restart marker is due: */ + restart = p_jpeg->restart_interval; /* count again */ + search_restart(&bs); /* align the bitstream */ + last_dc_val[0] = last_dc_val[1] = + last_dc_val[2] = 0; /* reset decoder */ + } + } /* for x */ + if (pf_progress != NULL) + pf_progress(y, p_jpeg->y_mbl-1); /* notify about decoding progress */ + } /* for y */ + + return 0; /* success */ +} + +#endif /* #ifdef HAVE_LCD_COLOR */ + /**************** end JPEG code ********************/ |