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/*C
(c) 2005 bl0rg.net
**/
#include "conf.h"
#include <stdio.h>
#include <errno.h>
#include <assert.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include "mp3.h"
#include "bv.h"
/*M
**/
int mp3_fill_si(mp3_frame_t *frame) {
assert(frame != NULL);
assert((frame->si_bitsize != 0) ||
"Trying to write an empty sideinfo");
unsigned char *ptr = frame->raw + 4;
if (frame->protected == 0)
ptr += 2;
bv_t bv;
bv_init(&bv, ptr, frame->si_bitsize);
mp3_si_t *si = &frame->si;
unsigned int nch = (frame->mode != 3) ? 2 : 1;
bv_put_bits(&bv, si->main_data_end, 9);
bv_put_bits(&bv, si->private_bits, nch == 2 ? 3 : 5);
unsigned int i;
for (i = 0; i < nch; i++) {
unsigned int band;
for (band = 0; band < 4; band++)
bv_put_bits(&bv, si->channel[i].scfsi[band], 1);
}
unsigned int gri;
for (gri = 0; gri < 2; gri++) {
for (i = 0; i < nch; i++) {
mp3_granule_t *gr = &si->channel[i].granule[gri];
bv_put_bits(&bv, gr->part2_3_length, 12);
bv_put_bits(&bv, gr->big_values, 9);
bv_put_bits(&bv, gr->global_gain, 8);
bv_put_bits(&bv, gr->scale_comp, 4);
bv_put_bits(&bv, gr->blocksplit_flag, 1);
if (gr->blocksplit_flag) {
bv_put_bits(&bv, gr->block_type, 2);
bv_put_bits(&bv, gr->switch_point, 1);
bv_put_bits(&bv, gr->tbl_sel[0], 5);
bv_put_bits(&bv, gr->tbl_sel[1], 5);
unsigned int j;
for (j = 0; j < 3; j++)
bv_put_bits(&bv, gr->sub_gain[j], 3);
} else {
unsigned int j;
for (j = 0; j < 3; j++)
bv_put_bits(&bv, gr->tbl_sel[j], 5);
bv_put_bits(&bv, gr->reg0_cnt, 4);
bv_put_bits(&bv, gr->reg1_cnt, 3);
}
bv_put_bits(&bv, gr->preflag, 1);
bv_put_bits(&bv, gr->scale_scale, 1);
bv_put_bits(&bv, gr->cnt1tbl_sel, 1);
}
}
assert((bv.len == bv.idx) || "Bitvector is not filled completely");
return 1;
}
extern unsigned long bitratetable[16];
extern unsigned short sampleratetable[4];
/*M
**/
int mp3_fill_hdr(mp3_frame_t *frame) {
assert(frame != NULL);
bv_t bv;
bv_init(&bv, frame->raw, 4 * 8);
bv_put_bits(&bv, 0xFFF, 12);
bv_put_bits(&bv, frame->id, 1);
bv_put_bits(&bv, frame->layer, 2);
bv_put_bits(&bv, frame->protected, 1);
bv_put_bits(&bv, frame->bitrate_index, 4);
bv_put_bits(&bv, frame->samplerfindex, 2);
bv_put_bits(&bv, frame->padding_bit, 1);
bv_put_bits(&bv, frame->private_bit, 1);
bv_put_bits(&bv, frame->mode, 2);
bv_put_bits(&bv, frame->mode_ext, 2);
bv_put_bits(&bv, frame->copyright, 1);
bv_put_bits(&bv, frame->original, 1);
bv_put_bits(&bv, frame->emphasis, 2);
if (frame->protected == 0) {
frame->raw[4] = frame->crc[0];
frame->raw[5] = frame->crc[1];
}
assert((bv.idx == bv.len) || "Bitvector is not filled completely");
mp3_calc_hdr(frame);
return 1;
}
/*M
**/
int mp3_write_frame(file_t *mp3, mp3_frame_t *frame) {
assert(mp3 != NULL);
assert(frame != NULL);
if (file_write(mp3, frame->raw, frame->frame_size) <= 0)
return EEOF;
return 1;
}
/*C
**/
#ifdef MP3_TEST
int main(int argc, char *argv[]) {
char *f[2];
if (!(f[0] = *++argv) || !(f[1] = *++argv)) {
fprintf(stderr, "Usage: mp3-write mp3in mp3out\n");
return 1;
}
mp3_file_t in;
if (!mp3_open_read(&in, f[0])) {
fprintf(stderr, "Could not open mp3 file for read: %s\n", f[0]);
return 1;
}
mp3_file_t out;
if (!mp3_open_write(&out, f[1])) {
fprintf(stderr, "Could not open mp3 file for write: %s\n", f[1]);
mp3_close(&in);
return 1;
}
mp3_frame_t frame;
while (mp3_next_frame(&in, &frame) > 0) {
memset(frame.raw, 0, 4 + frame.si_size);
if (!mp3_fill_hdr(&frame) ||
!mp3_fill_si(&frame) ||
(mp3_write_frame(&out, &frame) <= 0)) {
fprintf(stderr, "Could not write frame\n");
mp3_close(&in);
mp3_close(&out);
return 1;
}
}
mp3_close(&in);
mp3_close(&out);
return 0;
}
#endif
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