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supporting 4:2:2 vertical subsampling

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@4725 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jörg Hohensohn 2004-06-10 06:48:24 +00:00
parent 9bcc351dd2
commit 5fc1b64ae0
1 changed files with 87 additions and 64 deletions
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151
apps/plugins/jpeg.c
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@ -606,6 +606,7 @@ struct jpeg
int y_mbl; /* y dimension of MBL */
int blocks; /* blocks per MBL */
int restart_interval; /* number of MCUs between RSTm markers */
int store_pos[4]; /* for Y block ordering */
unsigned char* p_entropy_data;
unsigned char* p_entropy_end;
@ -688,67 +689,11 @@ int process_markers(unsigned char* p_src, long size, struct jpeg* p_jpeg)
p_jpeg->frameheader[i].horizontal_sampling = *p_src >> 4;
p_jpeg->frameheader[i].vertical_sampling = *p_src++ & 0x0F;
p_jpeg->frameheader[i].quanttable_select = *p_src++;
if (p_jpeg->frameheader[i].horizontal_sampling > 2
|| p_jpeg->frameheader[i].vertical_sampling > 2)
return -3; /* Unsupported SOF0 subsampling */
}
/* assignments for the decoding of blocks */
if (p_jpeg->frameheader[0].horizontal_sampling == 2
&& p_jpeg->frameheader[0].vertical_sampling == 1)
{ /* 4:2:2 */
p_jpeg->blocks = 4;
p_jpeg->x_mbl = (p_jpeg->x_size+15) / 16;
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[1] = 0;
p_jpeg->mcu_membership[2] = 2;
p_jpeg->mcu_membership[3] = 3;
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;
}
else if (p_jpeg->frameheader[0].horizontal_sampling == 2
&& p_jpeg->frameheader[0].vertical_sampling == 2)
{ /* 4:2:0 */
p_jpeg->blocks = 6;
p_jpeg->x_mbl = (p_jpeg->x_size+15) / 16;
p_jpeg->x_phys = p_jpeg->x_mbl * 16;
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;
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->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;
}
else if (p_jpeg->frameheader[0].horizontal_sampling == 1
&& p_jpeg->frameheader[0].vertical_sampling == 1)
{ /* 4:4:4 */
p_jpeg->blocks = n;
p_jpeg->x_mbl = (p_jpeg->x_size+7) / 8;
p_jpeg->x_phys = p_jpeg->x_mbl * 8;
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->tab_membership[0] = 0;
p_jpeg->tab_membership[1] = 1;
p_jpeg->tab_membership[2] = 1;
}
else
{
return(-3); /* Unsupported SOF0 subsampling */
}
p_jpeg->blocks = n;
}
break;
@ -1103,6 +1048,84 @@ void build_lut(struct jpeg* p_jpeg)
p_jpeg->qt_idct[0][zag[i]] = p_jpeg->quanttable[0][i];
p_jpeg->qt_idct[1][zag[i]] = p_jpeg->quanttable[1][i];
}
for (i=0; i<4; i++)
p_jpeg->store_pos[i] = i; /* default ordering */
/* assignments for the decoding of blocks */
if (p_jpeg->frameheader[0].horizontal_sampling == 2
&& p_jpeg->frameheader[0].vertical_sampling == 1)
{ /* 4:2:2 */
p_jpeg->blocks = 4;
p_jpeg->x_mbl = (p_jpeg->x_size+15) / 16;
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[1] = 0;
p_jpeg->mcu_membership[2] = 2;
p_jpeg->mcu_membership[3] = 3;
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;
}
if (p_jpeg->frameheader[0].horizontal_sampling == 1
&& p_jpeg->frameheader[0].vertical_sampling == 2)
{ /* 4:2:2 vertically subsampled */
p_jpeg->store_pos[1] = 2; /* block positions are mirrored */
p_jpeg->store_pos[2] = 1;
p_jpeg->blocks = 4;
p_jpeg->x_mbl = (p_jpeg->x_size+7) / 8;
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[1] = 0;
p_jpeg->mcu_membership[2] = 2;
p_jpeg->mcu_membership[3] = 3;
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;
}
else if (p_jpeg->frameheader[0].horizontal_sampling == 2
&& p_jpeg->frameheader[0].vertical_sampling == 2)
{ /* 4:2:0 */
p_jpeg->blocks = 6;
p_jpeg->x_mbl = (p_jpeg->x_size+15) / 16;
p_jpeg->x_phys = p_jpeg->x_mbl * 16;
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;
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->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;
}
else if (p_jpeg->frameheader[0].horizontal_sampling == 1
&& p_jpeg->frameheader[0].vertical_sampling == 1)
{ /* 4:4:4 */
/* don't overwrite p_jpeg->blocks */
p_jpeg->x_mbl = (p_jpeg->x_size+7) / 8;
p_jpeg->x_phys = p_jpeg->x_mbl * 8;
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->tab_membership[0] = 0;
p_jpeg->tab_membership[1] = 1;
p_jpeg->tab_membership[2] = 1;
}
}
@ -1333,10 +1356,10 @@ int jpeg_decode(struct jpeg* p_jpeg, unsigned char* p_pixel, int downscale,
skip_mcu = (width/p_jpeg->x_mbl);
/* prepare offsets about where to store the different blocks */
store_offs[0] = 0;
store_offs[1] = 8 / downscale; /* to the right */
store_offs[2] = width * 8 / downscale; /* below */
store_offs[3] = store_offs[1] + store_offs[2]; /* right+below */
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++)
{