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kolibrios/contrib/media/updf/pdf/pdf_function.c

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uPDF with buttons git-svn-id: svn://kolibrios.org@4680 a494cfbc-eb01-0410-851d-a64ba20cac60
2014-03-22 22:00:40 +01:00
#include "fitz.h"
#include "mupdf.h"
enum
{
MAXN = FZ_MAX_COLORS,
MAXM = FZ_MAX_COLORS,
};
typedef struct psobj_s psobj;
enum
{
SAMPLE = 0,
EXPONENTIAL = 2,
STITCHING = 3,
POSTSCRIPT = 4
};
struct pdf_function_s
{
int refs;
int type; /* 0=sample 2=exponential 3=stitching 4=postscript */
int m; /* number of input values */
int n; /* number of output values */
float domain[MAXM][2]; /* even index : min value, odd index : max value */
float range[MAXN][2]; /* even index : min value, odd index : max value */
int has_range;
union
{
struct {
unsigned short bps;
int size[MAXM];
float encode[MAXM][2];
float decode[MAXN][2];
float *samples;
} sa;
struct {
float n;
float c0[MAXN];
float c1[MAXN];
} e;
struct {
int k;
pdf_function **funcs; /* k */
float *bounds; /* k - 1 */
float *encode; /* k * 2 */
} st;
struct {
psobj *code;
int cap;
} p;
} u;
};
#define RADIAN 57.2957795
static inline float lerp(float x, float xmin, float xmax, float ymin, float ymax)
{
if (xmin == xmax)
return ymin;
if (ymin == ymax)
return ymin;
return ymin + (x - xmin) * (ymax - ymin) / (xmax - xmin);
}
/*
* PostScript calculator
*/
enum { PS_BOOL, PS_INT, PS_REAL, PS_OPERATOR, PS_BLOCK };
enum
{
PS_OP_ABS, PS_OP_ADD, PS_OP_AND, PS_OP_ATAN, PS_OP_BITSHIFT,
PS_OP_CEILING, PS_OP_COPY, PS_OP_COS, PS_OP_CVI, PS_OP_CVR,
PS_OP_DIV, PS_OP_DUP, PS_OP_EQ, PS_OP_EXCH, PS_OP_EXP,
PS_OP_FALSE, PS_OP_FLOOR, PS_OP_GE, PS_OP_GT, PS_OP_IDIV,
PS_OP_INDEX, PS_OP_LE, PS_OP_LN, PS_OP_LOG, PS_OP_LT, PS_OP_MOD,
PS_OP_MUL, PS_OP_NE, PS_OP_NEG, PS_OP_NOT, PS_OP_OR, PS_OP_POP,
PS_OP_ROLL, PS_OP_ROUND, PS_OP_SIN, PS_OP_SQRT, PS_OP_SUB,
PS_OP_TRUE, PS_OP_TRUNCATE, PS_OP_XOR, PS_OP_IF, PS_OP_IFELSE,
PS_OP_RETURN
};
static char *ps_op_names[] =
{
"abs", "add", "and", "atan", "bitshift", "ceiling", "copy",
"cos", "cvi", "cvr", "div", "dup", "eq", "exch", "exp",
"false", "floor", "ge", "gt", "idiv", "index", "le", "ln",
"log", "lt", "mod", "mul", "ne", "neg", "not", "or", "pop",
"roll", "round", "sin", "sqrt", "sub", "true", "truncate",
"xor", "if", "ifelse", "return"
};
struct psobj_s
{
int type;
union
{
int b; /* boolean (stack only) */
int i; /* integer (stack and code) */
float f; /* real (stack and code) */
int op; /* operator (code only) */
int block; /* if/ifelse block pointer (code only) */
} u;
};
typedef struct ps_stack_s ps_stack;
struct ps_stack_s
{
psobj stack[100];
int sp;
};
void
pdf_debug_ps_stack(ps_stack *st)
{
int i;
printf("stack: ");
for (i = 0; i < st->sp; i++)
{
switch (st->stack[i].type)
{
case PS_BOOL:
if (st->stack[i].u.b)
printf("true ");
else
printf("false ");
break;
case PS_INT:
printf("%d ", st->stack[i].u.i);
break;
case PS_REAL:
printf("%g ", st->stack[i].u.f);
break;
}
}
printf("\n");
}
static void
ps_init_stack(ps_stack *st)
{
memset(st->stack, 0, sizeof(st->stack));
st->sp = 0;
}
static inline int ps_overflow(ps_stack *st, int n)
{
return n < 0 || st->sp + n >= nelem(st->stack);
}
static inline int ps_underflow(ps_stack *st, int n)
{
return n < 0 || st->sp - n < 0;
}
static inline int ps_is_type(ps_stack *st, int t)
{
return !ps_underflow(st, 1) && st->stack[st->sp - 1].type == t;
}
static inline int ps_is_type2(ps_stack *st, int t)
{
return !ps_underflow(st, 2) && st->stack[st->sp - 1].type == t && st->stack[st->sp - 2].type == t;
}
static void
ps_push_bool(ps_stack *st, int b)
{
if (!ps_overflow(st, 1))
{
st->stack[st->sp].type = PS_BOOL;
st->stack[st->sp].u.b = b;
st->sp++;
}
}
static void
ps_push_int(ps_stack *st, int n)
{
if (!ps_overflow(st, 1))
{
st->stack[st->sp].type = PS_INT;
st->stack[st->sp].u.i = n;
st->sp++;
}
}
static void
ps_push_real(ps_stack *st, float n)
{
if (!ps_overflow(st, 1))
{
st->stack[st->sp].type = PS_REAL;
st->stack[st->sp].u.f = n;
st->sp++;
}
}
static int
ps_pop_bool(ps_stack *st)
{
if (!ps_underflow(st, 1))
{
if (ps_is_type(st, PS_BOOL))
return st->stack[--st->sp].u.b;
}
return 0;
}
static int
ps_pop_int(ps_stack *st)
{
if (!ps_underflow(st, 1))
{
if (ps_is_type(st, PS_INT))
return st->stack[--st->sp].u.i;
if (ps_is_type(st, PS_REAL))
return st->stack[--st->sp].u.f;
}
return 0;
}
static float
ps_pop_real(ps_stack *st)
{
if (!ps_underflow(st, 1))
{
if (ps_is_type(st, PS_INT))
return st->stack[--st->sp].u.i;
if (ps_is_type(st, PS_REAL))
return st->stack[--st->sp].u.f;
}
return 0;
}
static void
ps_copy(ps_stack *st, int n)
{
if (!ps_underflow(st, n) && !ps_overflow(st, n))
{
memcpy(st->stack + st->sp, st->stack + st->sp - n, n * sizeof(psobj));
st->sp += n;
}
}
static void
ps_roll(ps_stack *st, int n, int j)
{
psobj tmp;
int i;
if (ps_underflow(st, n) || j == 0 || n == 0)
return;
if (j >= 0)
{
j %= n;
}
else
{
j = -j % n;
if (j != 0)
j = n - j;
}
for (i = 0; i < j; i++)
{
tmp = st->stack[st->sp - 1];
memmove(st->stack + st->sp - n + 1, st->stack + st->sp - n, n * sizeof(psobj));
st->stack[st->sp - n] = tmp;
}
}
static void
ps_index(ps_stack *st, int n)
{
if (!ps_overflow(st, 1) && !ps_underflow(st, n))
{
st->stack[st->sp] = st->stack[st->sp - n - 1];
st->sp++;
}
}
static void
ps_run(psobj *code, ps_stack *st, int pc)
{
int i1, i2;
float r1, r2;
int b1, b2;
while (1)
{
switch (code[pc].type)
{
case PS_INT:
ps_push_int(st, code[pc++].u.i);
break;
case PS_REAL:
ps_push_real(st, code[pc++].u.f);
break;
case PS_OPERATOR:
switch (code[pc++].u.op)
{
case PS_OP_ABS:
if (ps_is_type(st, PS_INT))
ps_push_int(st, abs(ps_pop_int(st)));
else
ps_push_real(st, fabsf(ps_pop_real(st)));
break;
case PS_OP_ADD:
if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_int(st, i1 + i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_real(st, r1 + r2);
}
break;
case PS_OP_AND:
if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_int(st, i1 & i2);
}
else {
b2 = ps_pop_bool(st);
b1 = ps_pop_bool(st);
ps_push_bool(st, b1 && b2);
}
break;
case PS_OP_ATAN:
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
r1 = atan2f(r1, r2) * RADIAN;
if (r1 < 0)
r1 += 360;
ps_push_real(st, r1);
break;
case PS_OP_BITSHIFT:
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
if (i2 > 0)
ps_push_int(st, i1 << i2);
else if (i2 < 0)
ps_push_int(st, (int)((unsigned int)i1 >> i2));
else
ps_push_int(st, i1);
break;
case PS_OP_CEILING:
r1 = ps_pop_real(st);
ps_push_real(st, ceilf(r1));
break;
case PS_OP_COPY:
ps_copy(st, ps_pop_int(st));
break;
case PS_OP_COS:
r1 = ps_pop_real(st);
ps_push_real(st, cosf(r1/RADIAN));
break;
case PS_OP_CVI:
ps_push_int(st, ps_pop_int(st));
break;
case PS_OP_CVR:
ps_push_real(st, ps_pop_real(st));
break;
case PS_OP_DIV:
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_real(st, r1 / r2);
break;
case PS_OP_DUP:
ps_copy(st, 1);
break;
case PS_OP_EQ:
if (ps_is_type2(st, PS_BOOL)) {
b2 = ps_pop_bool(st);
b1 = ps_pop_bool(st);
ps_push_bool(st, b1 == b2);
}
else if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_bool(st, i1 == i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_bool(st, r1 == r2);
}
break;
case PS_OP_EXCH:
ps_roll(st, 2, 1);
break;
case PS_OP_EXP:
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_real(st, powf(r1, r2));
break;
case PS_OP_FALSE:
ps_push_bool(st, 0);
break;
case PS_OP_FLOOR:
r1 = ps_pop_real(st);
ps_push_real(st, floorf(r1));
break;
case PS_OP_GE:
if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_bool(st, i1 >= i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_bool(st, r1 >= r2);
}
break;
case PS_OP_GT:
if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_bool(st, i1 > i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_bool(st, r1 > r2);
}
break;
case PS_OP_IDIV:
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_int(st, i1 / i2);
break;
case PS_OP_INDEX:
ps_index(st, ps_pop_int(st));
break;
case PS_OP_LE:
if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_bool(st, i1 <= i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_bool(st, r1 <= r2);
}
break;
case PS_OP_LN:
r1 = ps_pop_real(st);
ps_push_real(st, logf(r1));
break;
case PS_OP_LOG:
r1 = ps_pop_real(st);
ps_push_real(st, log10f(r1));
break;
case PS_OP_LT:
if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_bool(st, i1 < i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_bool(st, r1 < r2);
}
break;
case PS_OP_MOD:
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_int(st, i1 % i2);
break;
case PS_OP_MUL:
if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_int(st, i1 * i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_real(st, r1 * r2);
}
break;
case PS_OP_NE:
if (ps_is_type2(st, PS_BOOL)) {
b2 = ps_pop_bool(st);
b1 = ps_pop_bool(st);
ps_push_bool(st, b1 != b2);
}
else if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_bool(st, i1 != i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_bool(st, r1 != r2);
}
break;
case PS_OP_NEG:
if (ps_is_type(st, PS_INT))
ps_push_int(st, -ps_pop_int(st));
else
ps_push_real(st, -ps_pop_real(st));
break;
case PS_OP_NOT:
if (ps_is_type(st, PS_BOOL))
ps_push_bool(st, !ps_pop_bool(st));
else
ps_push_int(st, ~ps_pop_int(st));
break;
case PS_OP_OR:
if (ps_is_type2(st, PS_BOOL)) {
b2 = ps_pop_bool(st);
b1 = ps_pop_bool(st);
ps_push_bool(st, b1 || b2);
}
else {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_int(st, i1 | i2);
}
break;
case PS_OP_POP:
if (!ps_underflow(st, 1))
st->sp--;
break;
case PS_OP_ROLL:
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_roll(st, i1, i2);
break;
case PS_OP_ROUND:
if (!ps_is_type(st, PS_INT)) {
r1 = ps_pop_real(st);
ps_push_real(st, (r1 >= 0) ? floorf(r1 + 0.5f) : ceilf(r1 - 0.5f));
}
break;
case PS_OP_SIN:
r1 = ps_pop_real(st);
ps_push_real(st, sinf(r1/RADIAN));
break;
case PS_OP_SQRT:
r1 = ps_pop_real(st);
ps_push_real(st, sqrtf(r1));
break;
case PS_OP_SUB:
if (ps_is_type2(st, PS_INT)) {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_int(st, i1 - i2);
}
else {
r2 = ps_pop_real(st);
r1 = ps_pop_real(st);
ps_push_real(st, r1 - r2);
}
break;
case PS_OP_TRUE:
ps_push_bool(st, 1);
break;
case PS_OP_TRUNCATE:
if (!ps_is_type(st, PS_INT)) {
r1 = ps_pop_real(st);
ps_push_real(st, (r1 >= 0) ? floorf(r1) : ceilf(r1));
}
break;
case PS_OP_XOR:
if (ps_is_type2(st, PS_BOOL)) {
b2 = ps_pop_bool(st);
b1 = ps_pop_bool(st);
ps_push_bool(st, b1 ^ b2);
}
else {
i2 = ps_pop_int(st);
i1 = ps_pop_int(st);
ps_push_int(st, i1 ^ i2);
}
break;
case PS_OP_IF:
b1 = ps_pop_bool(st);
if (b1)
ps_run(code, st, code[pc + 1].u.block);
pc = code[pc + 2].u.block;
break;
case PS_OP_IFELSE:
b1 = ps_pop_bool(st);
if (b1)
ps_run(code, st, code[pc + 1].u.block);
else
ps_run(code, st, code[pc + 0].u.block);
pc = code[pc + 2].u.block;
break;
case PS_OP_RETURN:
return;
default:
fz_warn("foreign operator in calculator function");
return;
}
break;
default:
fz_warn("foreign object in calculator function");
return;
}
}
}
static void
resize_code(pdf_function *func, int newsize)
{
if (newsize >= func->u.p.cap)
{
func->u.p.cap = func->u.p.cap + 64;
func->u.p.code = fz_realloc(func->u.p.code, func->u.p.cap, sizeof(psobj));
}
}
static fz_error
parse_code(pdf_function *func, fz_stream *stream, int *codeptr)
{
fz_error error;
char buf[64];
int len;
int tok;
int opptr, elseptr, ifptr;
int a, b, mid, cmp;
memset(buf, 0, sizeof(buf));
while (1)
{
error = pdf_lex(&tok, stream, buf, sizeof buf, &len);
if (error)
return fz_rethrow(error, "calculator function lexical error");
switch(tok)
{
case PDF_TOK_EOF:
return fz_throw("truncated calculator function");
case PDF_TOK_INT:
resize_code(func, *codeptr);
func->u.p.code[*codeptr].type = PS_INT;
func->u.p.code[*codeptr].u.i = atoi(buf);
++*codeptr;
break;
case PDF_TOK_REAL:
resize_code(func, *codeptr);
func->u.p.code[*codeptr].type = PS_REAL;
func->u.p.code[*codeptr].u.f = fz_atof(buf);
++*codeptr;
break;
case PDF_TOK_OPEN_BRACE:
opptr = *codeptr;
*codeptr += 4;
resize_code(func, *codeptr);
ifptr = *codeptr;
error = parse_code(func, stream, codeptr);
if (error)
return fz_rethrow(error, "error in 'if' branch");
error = pdf_lex(&tok, stream, buf, sizeof buf, &len);
if (error)
return fz_rethrow(error, "calculator function syntax error");
if (tok == PDF_TOK_OPEN_BRACE)
{
elseptr = *codeptr;
error = parse_code(func, stream, codeptr);
if (error)
return fz_rethrow(error, "error in 'else' branch");
error = pdf_lex(&tok, stream, buf, sizeof buf, &len);
if (error)
return fz_rethrow(error, "calculator function syntax error");
}
else
{
elseptr = -1;
}
if (tok == PDF_TOK_KEYWORD)
{
if (!strcmp(buf, "if"))
{
if (elseptr >= 0)
return fz_throw("too many branches for 'if'");
func->u.p.code[opptr].type = PS_OPERATOR;
func->u.p.code[opptr].u.op = PS_OP_IF;
func->u.p.code[opptr+2].type = PS_BLOCK;
func->u.p.code[opptr+2].u.block = ifptr;
func->u.p.code[opptr+3].type = PS_BLOCK;
func->u.p.code[opptr+3].u.block = *codeptr;
}
else if (!strcmp(buf, "ifelse"))
{
if (elseptr < 0)
return fz_throw("not enough branches for 'ifelse'");
func->u.p.code[opptr].type = PS_OPERATOR;
func->u.p.code[opptr].u.op = PS_OP_IFELSE;
func->u.p.code[opptr+1].type = PS_BLOCK;
func->u.p.code[opptr+1].u.block = elseptr;
func->u.p.code[opptr+2].type = PS_BLOCK;
func->u.p.code[opptr+2].u.block = ifptr;
func->u.p.code[opptr+3].type = PS_BLOCK;
func->u.p.code[opptr+3].u.block = *codeptr;
}
else
{
return fz_throw("unknown keyword in 'if-else' context: '%s'", buf);
}
}
else
{
return fz_throw("missing keyword in 'if-else' context");
}
break;
case PDF_TOK_CLOSE_BRACE:
resize_code(func, *codeptr);
func->u.p.code[*codeptr].type = PS_OPERATOR;
func->u.p.code[*codeptr].u.op = PS_OP_RETURN;
++*codeptr;
return fz_okay;
case PDF_TOK_KEYWORD:
cmp = -1;
a = -1;
b = nelem(ps_op_names);
while (b - a > 1)
{
mid = (a + b) / 2;
cmp = strcmp(buf, ps_op_names[mid]);
if (cmp > 0)
a = mid;
else if (cmp < 0)
b = mid;
else
a = b = mid;
}
if (cmp != 0)
return fz_throw("unknown operator: '%s'", buf);
resize_code(func, *codeptr);
func->u.p.code[*codeptr].type = PS_OPERATOR;
func->u.p.code[*codeptr].u.op = a;
++*codeptr;
break;
default:
return fz_throw("calculator function syntax error");
}
}
}
static fz_error
load_postscript_func(pdf_function *func, pdf_xref *xref, fz_obj *dict, int num, int gen)
{
fz_error error;
fz_stream *stream;
int codeptr;
char buf[64];
int tok;
int len;
error = pdf_open_stream(&stream, xref, num, gen);
if (error)
return fz_rethrow(error, "cannot open calculator function stream");
error = pdf_lex(&tok, stream, buf, sizeof buf, &len);
if (error)
{
fz_close(stream);
return fz_rethrow(error, "stream is not a calculator function");
}
if (tok != PDF_TOK_OPEN_BRACE)
{
fz_close(stream);
return fz_throw("stream is not a calculator function");
}
func->u.p.code = NULL;
func->u.p.cap = 0;
codeptr = 0;
error = parse_code(func, stream, &codeptr);
if (error)
{
fz_close(stream);
return fz_rethrow(error, "cannot parse calculator function (%d %d R)", num, gen);
}
fz_close(stream);
return fz_okay;
}
static void
eval_postscript_func(pdf_function *func, float *in, float *out)
{
ps_stack st;
float x;
int i;
ps_init_stack(&st);
for (i = 0; i < func->m; i++)
{
x = CLAMP(in[i], func->domain[i][0], func->domain[i][1]);
ps_push_real(&st, x);
}
ps_run(func->u.p.code, &st, 0);
for (i = func->n - 1; i >= 0; i--)
{
x = ps_pop_real(&st);
out[i] = CLAMP(x, func->range[i][0], func->range[i][1]);
}
}
/*
* Sample function
*/
static fz_error
load_sample_func(pdf_function *func, pdf_xref *xref, fz_obj *dict, int num, int gen)
{
fz_error error;
fz_stream *stream;
fz_obj *obj;
int samplecount;
int bps;
int i;
func->u.sa.samples = NULL;
obj = fz_dict_gets(dict, "Size");
if (!fz_is_array(obj) || fz_array_len(obj) != func->m)
return fz_throw("malformed /Size");
for (i = 0; i < func->m; i++)
func->u.sa.size[i] = fz_to_int(fz_array_get(obj, i));
obj = fz_dict_gets(dict, "BitsPerSample");
if (!fz_is_int(obj))
return fz_throw("malformed /BitsPerSample");
func->u.sa.bps = bps = fz_to_int(obj);
obj = fz_dict_gets(dict, "Encode");
if (fz_is_array(obj))
{
if (fz_array_len(obj) != func->m * 2)
return fz_throw("malformed /Encode");
for (i = 0; i < func->m; i++)
{
func->u.sa.encode[i][0] = fz_to_real(fz_array_get(obj, i*2+0));
func->u.sa.encode[i][1] = fz_to_real(fz_array_get(obj, i*2+1));
}
}
else
{
for (i = 0; i < func->m; i++)
{
func->u.sa.encode[i][0] = 0;
func->u.sa.encode[i][1] = func->u.sa.size[i] - 1;
}
}
obj = fz_dict_gets(dict, "Decode");
if (fz_is_array(obj))
{
if (fz_array_len(obj) != func->n * 2)
return fz_throw("malformed /Decode");
for (i = 0; i < func->n; i++)
{
func->u.sa.decode[i][0] = fz_to_real(fz_array_get(obj, i*2+0));
func->u.sa.decode[i][1] = fz_to_real(fz_array_get(obj, i*2+1));
}
}
else
{
for (i = 0; i < func->n; i++)
{
func->u.sa.decode[i][0] = func->range[i][0];
func->u.sa.decode[i][1] = func->range[i][1];
}
}
for (i = 0, samplecount = func->n; i < func->m; i++)
samplecount *= func->u.sa.size[i];
func->u.sa.samples = fz_calloc(samplecount, sizeof(float));
error = pdf_open_stream(&stream, xref, num, gen);
if (error)
return fz_rethrow(error, "cannot open samples stream (%d %d R)", num, gen);
/* read samples */
for (i = 0; i < samplecount; i++)
{
unsigned int x;
float s;
if (fz_is_eof_bits(stream))
{
fz_close(stream);
return fz_throw("truncated sample stream");
}
switch (bps)
{
case 1: s = fz_read_bits(stream, 1); break;
case 2: s = fz_read_bits(stream, 2) / 3.0f; break;
case 4: s = fz_read_bits(stream, 4) / 15.0f; break;
case 8: s = fz_read_byte(stream) / 255.0f; break;
case 12: s = fz_read_bits(stream, 12) / 4095.0f; break;
case 16:
x = fz_read_byte(stream) << 8;
x |= fz_read_byte(stream);
s = x / 65535.0f;
break;
case 24:
x = fz_read_byte(stream) << 16;
x |= fz_read_byte(stream) << 8;
x |= fz_read_byte(stream);
s = x / 16777215.0f;
break;
case 32:
x = fz_read_byte(stream) << 24;
x |= fz_read_byte(stream) << 16;
x |= fz_read_byte(stream) << 8;
x |= fz_read_byte(stream);
s = x / 4294967295.0f;
break;
default:
fz_close(stream);
return fz_throw("sample stream bit depth %d unsupported", bps);
}
func->u.sa.samples[i] = s;
}
fz_close(stream);
return fz_okay;
}
static float
interpolate_sample(pdf_function *func, int *scale, int *e0, int *e1, float *efrac, int dim, int idx)
{
float a, b;
int idx0, idx1;
idx0 = e0[dim] * scale[dim] + idx;
idx1 = e1[dim] * scale[dim] + idx;
if (dim == 0)
{
a = func->u.sa.samples[idx0];
b = func->u.sa.samples[idx1];
}
else
{
a = interpolate_sample(func, scale, e0, e1, efrac, dim - 1, idx0);
b = interpolate_sample(func, scale, e0, e1, efrac, dim - 1, idx1);
}
return a + (b - a) * efrac[dim];
}
static void
eval_sample_func(pdf_function *func, float *in, float *out)
{
int e0[MAXM], e1[MAXM], scale[MAXM];
float efrac[MAXM];
float x;
int i;
/* encode input coordinates */
for (i = 0; i < func->m; i++)
{
x = CLAMP(in[i], func->domain[i][0], func->domain[i][1]);
x = lerp(x, func->domain[i][0], func->domain[i][1],
func->u.sa.encode[i][0], func->u.sa.encode[i][1]);
x = CLAMP(x, 0, func->u.sa.size[i] - 1);
e0[i] = floorf(x);
e1[i] = ceilf(x);
efrac[i] = x - floorf(x);
}
scale[0] = func->n;
for (i = 1; i < func->m; i++)
scale[i] = scale[i - 1] * func->u.sa.size[i];
for (i = 0; i < func->n; i++)
{
if (func->m == 1)
{
float a = func->u.sa.samples[e0[0] * func->n + i];
float b = func->u.sa.samples[e1[0] * func->n + i];
float ab = a + (b - a) * efrac[0];
out[i] = lerp(ab, 0, 1, func->u.sa.decode[i][0], func->u.sa.decode[i][1]);
out[i] = CLAMP(out[i], func->range[i][0], func->range[i][1]);
}
else if (func->m == 2)
{
int s0 = func->n;
int s1 = s0 * func->u.sa.size[0];
float a = func->u.sa.samples[e0[0] * s0 + e0[1] * s1 + i];
float b = func->u.sa.samples[e1[0] * s0 + e0[1] * s1 + i];
float c = func->u.sa.samples[e0[0] * s0 + e1[1] * s1 + i];
float d = func->u.sa.samples[e1[0] * s0 + e1[1] * s1 + i];
float ab = a + (b - a) * efrac[0];
float cd = c + (d - c) * efrac[0];
float abcd = ab + (cd - ab) * efrac[1];
out[i] = lerp(abcd, 0, 1, func->u.sa.decode[i][0], func->u.sa.decode[i][1]);
out[i] = CLAMP(out[i], func->range[i][0], func->range[i][1]);
}
else
{
float x = interpolate_sample(func, scale, e0, e1, efrac, func->m - 1, i);
out[i] = lerp(x, 0, 1, func->u.sa.decode[i][0], func->u.sa.decode[i][1]);
out[i] = CLAMP(out[i], func->range[i][0], func->range[i][1]);
}
}
}
/*
* Exponential function
*/
static fz_error
load_exponential_func(pdf_function *func, fz_obj *dict)
{
fz_obj *obj;
int i;
if (func->m != 1)
return fz_throw("/Domain must be one dimension (%d)", func->m);
obj = fz_dict_gets(dict, "N");
if (!fz_is_int(obj) && !fz_is_real(obj))
return fz_throw("malformed /N");
func->u.e.n = fz_to_real(obj);
obj = fz_dict_gets(dict, "C0");
if (fz_is_array(obj))
{
func->n = fz_array_len(obj);
if (func->n >= MAXN)
return fz_throw("exponential function result array out of range");
for (i = 0; i < func->n; i++)
func->u.e.c0[i] = fz_to_real(fz_array_get(obj, i));
}
else
{
func->n = 1;
func->u.e.c0[0] = 0;
}
obj = fz_dict_gets(dict, "C1");
if (fz_is_array(obj))
{
if (fz_array_len(obj) != func->n)
return fz_throw("/C1 must match /C0 length");
for (i = 0; i < func->n; i++)
func->u.e.c1[i] = fz_to_real(fz_array_get(obj, i));
}
else
{
if (func->n != 1)
return fz_throw("/C1 must match /C0 length");
func->u.e.c1[0] = 1;
}
return fz_okay;
}
static void
eval_exponential_func(pdf_function *func, float in, float *out)
{
float x = in;
float tmp;
int i;
x = CLAMP(x, func->domain[0][0], func->domain[0][1]);
/* constraint */
if ((func->u.e.n != (int)func->u.e.n && x < 0) || (func->u.e.n < 0 && x == 0))
{
fz_warn("constraint error");
return;
}
tmp = powf(x, func->u.e.n);
for (i = 0; i < func->n; i++)
{
out[i] = func->u.e.c0[i] + tmp * (func->u.e.c1[i] - func->u.e.c0[i]);
if (func->has_range)
out[i] = CLAMP(out[i], func->range[i][0], func->range[i][1]);
}
}
/*
* Stitching function
*/
static fz_error
load_stitching_func(pdf_function *func, pdf_xref *xref, fz_obj *dict)
{
pdf_function **funcs;
fz_error error;
fz_obj *obj;
fz_obj *sub;
fz_obj *num;
int k;
int i;
func->u.st.k = 0;
if (func->m != 1)
return fz_throw("/Domain must be one dimension (%d)", func->m);
obj = fz_dict_gets(dict, "Functions");
if (!fz_is_array(obj))
return fz_throw("stitching function has no input functions");
{
k = fz_array_len(obj);
func->u.st.funcs = fz_calloc(k, sizeof(pdf_function*));
func->u.st.bounds = fz_calloc(k - 1, sizeof(float));
func->u.st.encode = fz_calloc(k * 2, sizeof(float));
funcs = func->u.st.funcs;
for (i = 0; i < k; i++)
{
sub = fz_array_get(obj, i);
error = pdf_load_function(&funcs[i], xref, sub);
if (error)
return fz_rethrow(error, "cannot load sub function %d (%d %d R)", i, fz_to_num(sub), fz_to_gen(sub));
if (funcs[i]->m != 1 || funcs[i]->n != funcs[0]->n)
return fz_throw("sub function %d /Domain or /Range mismatch", i);
func->u.st.k ++;
}
if (!func->n)
func->n = funcs[0]->n;
else if (func->n != funcs[0]->n)
return fz_throw("sub function /Domain or /Range mismatch");
}
obj = fz_dict_gets(dict, "Bounds");
if (!fz_is_array(obj))
return fz_throw("stitching function has no bounds");
{
if (!fz_is_array(obj) || fz_array_len(obj) != k - 1)
return fz_throw("malformed /Bounds (not array or wrong length)");
for (i = 0; i < k-1; i++)
{
num = fz_array_get(obj, i);
if (!fz_is_int(num) && !fz_is_real(num))
return fz_throw("malformed /Bounds (item not real)");
func->u.st.bounds[i] = fz_to_real(num);
if (i && func->u.st.bounds[i-1] > func->u.st.bounds[i])
return fz_throw("malformed /Bounds (item not monotonic)");
}
if (k != 1 && (func->domain[0][0] > func->u.st.bounds[0] ||
func->domain[0][1] < func->u.st.bounds[k-2]))
fz_warn("malformed shading function bounds (domain mismatch), proceeding anyway.");
}
obj = fz_dict_gets(dict, "Encode");
if (!fz_is_array(obj))
return fz_throw("stitching function is missing encoding");
{
if (!fz_is_array(obj) || fz_array_len(obj) != k * 2)
return fz_throw("malformed /Encode");
for (i = 0; i < k; i++)
{
func->u.st.encode[i*2+0] = fz_to_real(fz_array_get(obj, i*2+0));
func->u.st.encode[i*2+1] = fz_to_real(fz_array_get(obj, i*2+1));
}
}
return fz_okay;
}
static void
eval_stitching_func(pdf_function *func, float in, float *out)
{
float low, high;
int k = func->u.st.k;
float *bounds = func->u.st.bounds;
int i;
in = CLAMP(in, func->domain[0][0], func->domain[0][1]);
for (i = 0; i < k - 1; i++)
{
if (in < bounds[i])
break;
}
if (i == 0 && k == 1)
{
low = func->domain[0][0];
high = func->domain[0][1];
}
else if (i == 0)
{
low = func->domain[0][0];
high = bounds[0];
}
else if (i == k - 1)
{
low = bounds[k-2];
high = func->domain[0][1];
}
else
{
low = bounds[i-1];
high = bounds[i];
}
in = lerp(in, low, high, func->u.st.encode[i*2+0], func->u.st.encode[i*2+1]);
pdf_eval_function(func->u.st.funcs[i], &in, 1, out, func->n);
}
/*
* Common
*/
pdf_function *
pdf_keep_function(pdf_function *func)
{
func->refs ++;
return func;
}
void
pdf_drop_function(pdf_function *func)
{
int i;
if (--func->refs == 0)
{
switch(func->type)
{
case SAMPLE:
fz_free(func->u.sa.samples);
break;
case EXPONENTIAL:
break;
case STITCHING:
for (i = 0; i < func->u.st.k; i++)
pdf_drop_function(func->u.st.funcs[i]);
fz_free(func->u.st.funcs);
fz_free(func->u.st.bounds);
fz_free(func->u.st.encode);
break;
case POSTSCRIPT:
fz_free(func->u.p.code);
break;
}
fz_free(func);
}
}
fz_error
pdf_load_function(pdf_function **funcp, pdf_xref *xref, fz_obj *dict)
{
fz_error error;
pdf_function *func;
fz_obj *obj;
int i;
if ((*funcp = pdf_find_item(xref->store, pdf_drop_function, dict)))
{
pdf_keep_function(*funcp);
return fz_okay;
}
func = fz_malloc(sizeof(pdf_function));
memset(func, 0, sizeof(pdf_function));
func->refs = 1;
obj = fz_dict_gets(dict, "FunctionType");
func->type = fz_to_int(obj);
/* required for all */
obj = fz_dict_gets(dict, "Domain");
func->m = fz_array_len(obj) / 2;
for (i = 0; i < func->m; i++)
{
func->domain[i][0] = fz_to_real(fz_array_get(obj, i * 2 + 0));
func->domain[i][1] = fz_to_real(fz_array_get(obj, i * 2 + 1));
}
/* required for type0 and type4, optional otherwise */
obj = fz_dict_gets(dict, "Range");
if (fz_is_array(obj))
{
func->has_range = 1;
func->n = fz_array_len(obj) / 2;
for (i = 0; i < func->n; i++)
{
func->range[i][0] = fz_to_real(fz_array_get(obj, i * 2 + 0));
func->range[i][1] = fz_to_real(fz_array_get(obj, i * 2 + 1));
}
}
else
{
func->has_range = 0;
func->n = 0;
}
if (func->m >= MAXM || func->n >= MAXN)
{
fz_free(func);
return fz_throw("assert: /Domain or /Range too big");
}
switch(func->type)
{
case SAMPLE:
error = load_sample_func(func, xref, dict, fz_to_num(dict), fz_to_gen(dict));
if (error)
{
pdf_drop_function(func);
return fz_rethrow(error, "cannot load sampled function (%d %d R)", fz_to_num(dict), fz_to_gen(dict));
}
break;
case EXPONENTIAL:
error = load_exponential_func(func, dict);
if (error)
{
pdf_drop_function(func);
return fz_rethrow(error, "cannot load exponential function (%d %d R)", fz_to_num(dict), fz_to_gen(dict));
}
break;
case STITCHING:
error = load_stitching_func(func, xref, dict);
if (error)
{
pdf_drop_function(func);
return fz_rethrow(error, "cannot load stitching function (%d %d R)", fz_to_num(dict), fz_to_gen(dict));
}
break;
case POSTSCRIPT:
error = load_postscript_func(func, xref, dict, fz_to_num(dict), fz_to_gen(dict));
if (error)
{
pdf_drop_function(func);
return fz_rethrow(error, "cannot load calculator function (%d %d R)", fz_to_num(dict), fz_to_gen(dict));
}
break;
default:
fz_free(func);
return fz_throw("unknown function type (%d %d R)", fz_to_num(dict), fz_to_gen(dict));
}
pdf_store_item(xref->store, pdf_keep_function, pdf_drop_function, dict, func);
*funcp = func;
return fz_okay;
}
void
pdf_eval_function(pdf_function *func, float *in, int inlen, float *out, int outlen)
{
memset(out, 0, sizeof(float) * outlen);
if (inlen != func->m)
{
fz_warn("tried to evaluate function with wrong number of inputs");
return;
}
if (func->n != outlen)
{
fz_warn("tried to evaluate function with wrong number of outputs");
return;
}
switch(func->type)
{
case SAMPLE: eval_sample_func(func, in, out); break;
case EXPONENTIAL: eval_exponential_func(func, *in, out); break;
case STITCHING: eval_stitching_func(func, *in, out); break;
case POSTSCRIPT: eval_postscript_func(func, in, out); break;
}
}
/*
* Debugging prints
*/
static void
pdf_debug_indent(char *prefix, int level, char *suffix)
{
int i;
printf("%s", prefix);
for (i = 0; i < level; i++)
printf("\t");
printf("%s", suffix);
}
static void
pdf_debug_ps_func_code(psobj *funccode, psobj *code, int level)
{
int eof, wasop;
pdf_debug_indent("", level, "{");
/* Print empty blocks as { }, instead of separating braces on different lines. */
if (code->type == PS_OPERATOR && code->u.op == PS_OP_RETURN)
{
printf(" } ");
return;
}
pdf_debug_indent("\n", ++level, "");
eof = 0;
wasop = 0;
while (!eof)
{
switch (code->type)
{
case PS_INT:
if (wasop)
pdf_debug_indent("\n", level, "");
printf("%d ", code->u.i);
wasop = 0;
code++;
break;
case PS_REAL:
if (wasop)
pdf_debug_indent("\n", level, "");
printf("%g ", code->u.f);
wasop = 0;
code++;
break;
case PS_OPERATOR:
if (code->u.op == PS_OP_RETURN)
{
printf("\n");
eof = 1;
}
else if (code->u.op == PS_OP_IF)
{
printf("\n");
pdf_debug_ps_func_code(funccode, &funccode[(code + 2)->u.block], level);
printf("%s", ps_op_names[code->u.op]);
code = &funccode[(code + 3)->u.block];
if (code->type != PS_OPERATOR || code->u.op != PS_OP_RETURN)
pdf_debug_indent("\n", level, "");
wasop = 0;
}
else if (code->u.op == PS_OP_IFELSE)
{
printf("\n");
pdf_debug_ps_func_code(funccode, &funccode[(code + 2)->u.block], level);
printf("\n");
pdf_debug_ps_func_code(funccode, &funccode[(code + 1)->u.block], level);
printf("%s", ps_op_names[code->u.op]);
code = &funccode[(code + 3)->u.block];
if (code->type != PS_OPERATOR || code->u.op != PS_OP_RETURN)
pdf_debug_indent("\n", level, "");
wasop = 0;
}
else
{
printf("%s ", ps_op_names[code->u.op]);
code++;
wasop = 1;
}
break;
}
}
pdf_debug_indent("", --level, "} ");
}
static void
pdf_debug_function_imp(pdf_function *func, int level)
{
int i;
pdf_debug_indent("", level, "function {\n");
pdf_debug_indent("", ++level, "");
switch (func->type)
{
case SAMPLE:
printf("sampled");
break;
case EXPONENTIAL:
printf("exponential");
break;
case STITCHING:
printf("stitching");
break;
case POSTSCRIPT:
printf("postscript");
break;
}
pdf_debug_indent("\n", level, "");
printf("%d input -> %d output\n", func->m, func->n);
pdf_debug_indent("", level, "domain ");
for (i = 0; i < func->m; i++)
printf("%g %g ", func->domain[i][0], func->domain[i][1]);
printf("\n");
if (func->has_range)
{
pdf_debug_indent("", level, "range ");
for (i = 0; i < func->n; i++)
printf("%g %g ", func->range[i][0], func->range[i][1]);
printf("\n");
}
switch (func->type)
{
case SAMPLE:
pdf_debug_indent("", level, "");
printf("bps: %d\n", func->u.sa.bps);
pdf_debug_indent("", level, "");
printf("size: [ ");
for (i = 0; i < func->m; i++)
printf("%d ", func->u.sa.size[i]);
printf("]\n");
pdf_debug_indent("", level, "");
printf("encode: [ ");
for (i = 0; i < func->m; i++)
printf("%g %g ", func->u.sa.encode[i][0], func->u.sa.encode[i][1]);
printf("]\n");
pdf_debug_indent("", level, "");
printf("decode: [ ");
for (i = 0; i < func->m; i++)
printf("%g %g ", func->u.sa.decode[i][0], func->u.sa.decode[i][1]);
printf("]\n");
break;
case EXPONENTIAL:
pdf_debug_indent("", level, "");
printf("n: %g\n", func->u.e.n);
pdf_debug_indent("", level, "");
printf("c0: [ ");
for (i = 0; i < func->n; i++)
printf("%g ", func->u.e.c0[i]);
printf("]\n");
pdf_debug_indent("", level, "");
printf("c1: [ ");
for (i = 0; i < func->n; i++)
printf("%g ", func->u.e.c1[i]);
printf("]\n");
break;
case STITCHING:
pdf_debug_indent("", level, "");
printf("%d functions\n", func->u.st.k);
pdf_debug_indent("", level, "");
printf("bounds: [ ");
for (i = 0; i < func->u.st.k - 1; i++)
printf("%g ", func->u.st.bounds[i]);
printf("]\n");
pdf_debug_indent("", level, "");
printf("encode: [ ");
for (i = 0; i < func->u.st.k * 2; i++)
printf("%g ", func->u.st.encode[i]);
printf("]\n");
for (i = 0; i < func->u.st.k; i++)
pdf_debug_function_imp(func->u.st.funcs[i], level);
break;
case POSTSCRIPT:
pdf_debug_ps_func_code(func->u.p.code, func->u.p.code, level);
printf("\n");
break;
}
pdf_debug_indent("", --level, "}\n");
}
void
pdf_debug_function(pdf_function *func)
{
pdf_debug_function_imp(func, 0);
}
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