dref.c

MPEG-4编解码的实现(包括MPEG4视音频编解码)

#include "quicktime.h"

int quicktime_dref_table_init(quicktime_dref_table_t *table)
{
	table->size = 0;
	table->type[0] = 'a';
	table->type[1] = 'l';
	table->type[2] = 'i';
	table->type[3] = 's';
	table->version = 0;
	table->flags = 0x0001;
	table->data_reference = malloc(256);
	table->data_reference[0] = 0;
}

int quicktime_dref_table_delete(quicktime_dref_table_t *table)
{
	if(table->data_reference) free(table->data_reference);
	table->data_reference = 0;
}

int quicktime_read_dref_table(quicktime_t *file, quicktime_dref_table_t *table)
{
	table->size = quicktime_read_int32(file);
	quicktime_read_char32(file, table->type);
	table->version = quicktime_read_char(file);
	table->flags = quicktime_read_int24(file);
	if(table->data_reference) free(table->data_reference);

	table->data_reference = malloc(table->size);
	if(table->size > 12)
		quicktime_read_data(file, table->data_reference, table->size - 12);
	table->data_reference[table->size - 12] = 0;
}

int quicktime_write_dref_table(quicktime_t *file, quicktime_dref_table_t *table)
{
	int len = strlen(table->data_reference);
	quicktime_write_int32(file, 12 + len);
	quicktime_write_char32(file, table->type);
	quicktime_write_char(file, table->version);
	quicktime_write_int24(file, table->flags);
	if(len)
		quicktime_write_data(file, table->data_reference, len);
}

int quicktime_dref_table_dump(quicktime_dref_table_t *table)
{
	printf("      data reference table (dref)\n");
	printf("       type %c%c%c%c\n", table->type[0], table->type[1], table->type[2], table->type[3]);
	printf("       version %d\n", table->version);
	printf("       flags %d\n", table->flags);
	printf("       data %s\n", table->data_reference);
}


int quicktime_dref_init(quicktime_dref_t *dref)
{
	dref->version = 0;
	dref->flags = 0;
	dref->total_entries = 0;
	dref->table = 0;
}

int quicktime_dref_init_all(quicktime_dref_t *dref)
{
	if(!dref->total_entries)
	{
		dref->total_entries = 1;
		dref->table = (quicktime_dref_table_t *)malloc(sizeof(quicktime_dref_table_t) * dref->total_entries);
		quicktime_dref_table_init(&(dref->table[0]));
	}
}

int quicktime_dref_delete(quicktime_dref_t *dref)
{
	if(dref->table)
	{
		int i;
		for(i = 0; i < dref->total_entries; i++)
			quicktime_dref_table_delete(&(dref->table[i]));
		free(dref->table);
	}
	dref->total_entries = 0;
}

int quicktime_dref_dump(quicktime_dref_t *dref)
{
	int i;
	
	printf("     data reference (dref)\n");
	printf("      version %d\n", dref->version);
	printf("      flags %d\n", dref->flags);
	for(i = 0; i < dref->total_entries; i++)
	{
		quicktime_dref_table_dump(&(dref->table[i]));
	}
}

int quicktime_read_dref(quicktime_t *file, quicktime_dref_t *dref)
{
	int i;

	dref->version = quicktime_read_char(file);
	dref->flags = quicktime_read_int24(file);
	dref->total_entries = quicktime_read_int32(file);
	dref->table = (quicktime_dref_table_t*)malloc(sizeof(quicktime_dref_table_t) * dref->total_entries);
	for(i = 0; i < dref->total_entries; i++)
	{
		quicktime_dref_table_init(&(dref->table[i]));
		quicktime_read_dref_table(file, &(dref->table[i]));
	}
}

int quicktime_write_dref(quicktime_t *file, quicktime_dref_t *dref)
{
	int i;
	quicktime_atom_t atom;
	quicktime_atom_write_header(file, &atom, "dref");

	quicktime_write_char(file, dref->version);
	quicktime_write_int24(file, dref->flags);
	quicktime_write_int32(file, dref->total_entries);

	for(i = 0; i < dref->total_entries; i++)
	{
		quicktime_write_dref_table(file, &(dref->table[i]));
	}
	quicktime_atom_write_footer(file, &atom);
}