* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
*/
/**
- * @file imc.c IMC - Intel Music Coder
+ * @file libavcodec/imc.c IMC - Intel Music Coder
* A mdct based codec using a 256 points large transform
* divied into 32 bands with some mix of scale factors.
* Only mono is supported.
#define ALT_BITSTREAM_READER
#include "avcodec.h"
-#include "bitstream.h"
+#include "get_bits.h"
#include "dsputil.h"
#include "imcdata.h"
+#define IMC_BLOCK_SIZE 64
#define IMC_FRAME_ID 0x21
#define BANDS 32
#define COEFFS 256
int codewords[COEFFS]; ///< raw codewords read from bitstream
float sqrt_tab[30];
GetBitContext gb;
- VLC huffman_vlc[4][4];
- float flcf1, flcf2;
int decoder_reset;
float one_div_log2;
DECLARE_ALIGNED_16(float, out_samples[COEFFS]);
} IMCContext;
+static VLC huffman_vlc[4][4];
+
+#define VLC_TABLES_SIZE 9512
+
+static const int vlc_offsets[17] = {
+ 0, 640, 1156, 1732, 2308, 2852, 3396, 3924,
+ 4452, 5220, 5860, 6628, 7268, 7908, 8424, 8936, VLC_TABLES_SIZE};
-static int imc_decode_init(AVCodecContext * avctx)
+static VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2];
+
+static av_cold int imc_decode_init(AVCodecContext * avctx)
{
int i, j;
IMCContext *q = avctx->priv_data;
q->old_floor[i] = 1.0;
/* Build mdct window, a simple sine window normalized with sqrt(2) */
+ ff_sine_window_init(q->mdct_sine_window, COEFFS);
for(i = 0; i < COEFFS; i++)
- q->mdct_sine_window[i] = sin((i + 0.5) / 512.0 * M_PI) * sqrt(2.0);
+ q->mdct_sine_window[i] *= sqrt(2.0);
for(i = 0; i < COEFFS/2; i++){
q->post_cos[i] = cos(i / 256.0 * M_PI);
q->post_sin[i] = sin(i / 256.0 * M_PI);
q->last_fft_im[i] = 0;
}
- q->flcf1 = log2(10) * 0.05703125;
- q->flcf2 = log2(10) * 0.25;
/* Generate a square root table */
/* initialize the VLC tables */
for(i = 0; i < 4 ; i++) {
for(j = 0; j < 4; j++) {
- init_vlc (&q->huffman_vlc[i][j], 9, imc_huffman_sizes[i],
+ huffman_vlc[i][j].table = &vlc_tables[vlc_offsets[i * 4 + j]];
+ huffman_vlc[i][j].table_allocated = vlc_offsets[i * 4 + j + 1] - vlc_offsets[i * 4 + j];
+ init_vlc(&huffman_vlc[i][j], 9, imc_huffman_sizes[i],
imc_huffman_lens[i][j], 1, 1,
- imc_huffman_bits[i][j], 2, 2, 0);
+ imc_huffman_bits[i][j], 2, 2, INIT_VLC_USE_NEW_STATIC);
}
}
q->one_div_log2 = 1/log(2);
ff_fft_init(&q->fft, 7, 1);
dsputil_init(&q->dsp, avctx);
+ avctx->sample_fmt = SAMPLE_FMT_S16;
+ avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
return 0;
}
int s;
s = stream_format_code >> 1;
- hufftab[0] = &q->huffman_vlc[s][0];
- hufftab[1] = &q->huffman_vlc[s][1];
- hufftab[2] = &q->huffman_vlc[s][2];
- hufftab[3] = &q->huffman_vlc[s][3];
+ hufftab[0] = &huffman_vlc[s][0];
+ hufftab[1] = &huffman_vlc[s][1];
+ hufftab[2] = &huffman_vlc[s][2];
+ hufftab[3] = &huffman_vlc[s][3];
cb_sel = imc_cb_select[s];
if(stream_format_code & 4)
float tmp, tmp2;
//maybe some frequency division thingy
- flcoeffs1[0] = 20000.0 / pow (2, levlCoeffBuf[0] * q->flcf1);
- flcoeffs2[0] = log2(flcoeffs1[0]);
+ flcoeffs1[0] = 20000.0 / pow (2, levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
+ flcoeffs2[0] = log(flcoeffs1[0])/log(2);
tmp = flcoeffs1[0];
tmp2 = flcoeffs2[0];
level -=16;
tmp *= imc_exp_tab[15 + level];
- tmp2 += q->flcf2 * level;
+ tmp2 += 0.83048 * level; // 0.83048 = log2(10) * 0.25
flcoeffs1[i] = tmp;
flcoeffs2[i] = tmp2;
}
flcoeffs1[i] = 0;
if(levlCoeffBuf[i] < 16) {
flcoeffs1[i] = imc_exp_tab2[levlCoeffBuf[i]] * old_floor[i];
- flcoeffs2[i] = (levlCoeffBuf[i]-7) * q->flcf2 + flcoeffs2[i];
+ flcoeffs2[i] = (levlCoeffBuf[i]-7) * 0.83048 + flcoeffs2[i]; // 0.83048 = log2(10) * 0.25
} else {
flcoeffs1[i] = old_floor[i];
}
highest = FFMAX(highest, q->flcoeffs1[i]);
for(i = 0; i < BANDS-1; i++) {
- q->flcoeffs4[i] = q->flcoeffs3[i] - log2(q->flcoeffs5[i]);
+ q->flcoeffs4[i] = q->flcoeffs3[i] - log(q->flcoeffs5[i])/log(2);
}
q->flcoeffs4[BANDS - 1] = limit;
iacc = 0;
for(j = (stream_format_code & 0x2)?4:0; j < BANDS; j++) {
- cwlen = clip((int)((q->flcoeffs4[j] * 0.5) - summa + 0.5), 0, 6);
+ cwlen = av_clip((int)((q->flcoeffs4[j] * 0.5) - summa + 0.5), 0, 6);
q->bitsBandT[j] = cwlen;
summer += q->bandWidthT[j] * cwlen;
q->skipFlagBits[i] = band_tab[i+1] - band_tab[i];
for(j = band_tab[i]; j < band_tab[i+1]; j++) {
- if ((q->skipFlags[j] = get_bits(&q->gb,1)))
+ if ((q->skipFlags[j] = get_bits1(&q->gb)))
q->skipFlagCount[i]++;
}
} else {
if (j < band_tab[i+1]) {
q->skipFlagBits[i]++;
- if ((q->skipFlags[j] = get_bits(&q->gb,1)))
+ if ((q->skipFlags[j] = get_bits1(&q->gb)))
q->skipFlagCount[i]++;
}
}
}
}
-void imc_imdct256(IMCContext *q) {
+static void imc_imdct256(IMCContext *q) {
int i;
float re, im;
static int imc_decode_frame(AVCodecContext * avctx,
void *data, int *data_size,
- uint8_t * buf, int buf_size)
+ AVPacket *avpkt)
{
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
IMCContext *q = avctx->priv_data;
int flag;
int bits, summer;
int counter, bitscount;
- uint16_t *buf16 = (uint16_t *) buf;
+ uint16_t buf16[IMC_BLOCK_SIZE / 2];
- /* FIXME: input should not be modified */
- for(i = 0; i < FFMIN(buf_size, avctx->block_align) / 2; i++)
- buf16[i] = bswap_16(buf16[i]);
+ if (buf_size < IMC_BLOCK_SIZE) {
+ av_log(avctx, AV_LOG_ERROR, "imc frame too small!\n");
+ return -1;
+ }
+ for(i = 0; i < IMC_BLOCK_SIZE / 2; i++)
+ buf16[i] = bswap_16(((const uint16_t*)buf)[i]);
- init_get_bits(&q->gb, buf, 512);
+ init_get_bits(&q->gb, (const uint8_t*)buf16, IMC_BLOCK_SIZE * 8);
/* Check the frame header */
imc_hdr = get_bits(&q->gb, 9);
*data_size = COEFFS * sizeof(int16_t);
- return avctx->block_align;
+ return IMC_BLOCK_SIZE;
}
-static int imc_decode_close(AVCodecContext * avctx)
+static av_cold int imc_decode_close(AVCodecContext * avctx)
{
IMCContext *q = avctx->priv_data;
.init = imc_decode_init,
.close = imc_decode_close,
.decode = imc_decode_frame,
+ .long_name = NULL_IF_CONFIG_SMALL("IMC (Intel Music Coder)"),
};
projects / frescor / ffmpeg.git / blobdiff