ref: 8e9935e445dd2988b93a5d0410c0344e9efac506
parent: 91c3d6d0e3f82f9ffddd3fd2e95ea7fafb403111
author: menno <menno>
date: Sun Sep 29 06:34:00 EDT 2002
Actual reverse RVLC, but doesn't work yet problems with the escapes
--- a/libfaad/bits.c
+++ b/libfaad/bits.c
@@ -16,7 +16,7 @@
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
**
-** $Id: bits.c,v 1.11 2002/09/28 21:57:37 menno Exp $
+** $Id: bits.c,v 1.12 2002/09/29 10:34:00 menno Exp $
**/
#include "common.h"
@@ -94,10 +94,10 @@
void faad_initbits_rev(bitfile *ld, void *buffer,
uint32_t bits_in_buffer)
{- uint32_t tmp, index;
+ uint32_t tmp;
+ int32_t index;
- index = (bits_in_buffer+31)/32;
- index--;
+ index = (bits_in_buffer+31)/32 - 1;
ld->start = (uint32_t*)buffer + index - 2;
--- a/libfaad/rvlc_scale_factors.c
+++ b/libfaad/rvlc_scale_factors.c
@@ -16,9 +16,22 @@
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
**
-** $Id: rvlc_scale_factors.c,v 1.4 2002/09/16 20:43:37 menno Exp $
+** $Id: rvlc_scale_factors.c,v 1.5 2002/09/29 10:34:00 menno Exp $
**/
+/* RVLC scalefactor decoding
+ *
+ * RVLC works like this:
+ * 1. Only symmetric huffman codewords are used
+ * 2. Total length of the scalefactor data is stored in the bitsream
+ * 3. Scalefactors are DPCM coded
+ * 4. Next to the starting value for DPCM the ending value is also stored
+ *
+ * With all this it is possible to read the scalefactor data from 2 sides.
+ * If there is a bit error in the scalefactor data it is possible to start
+ * decoding from the other end of the data, to find all but 1 scalefactor.
+ */
+
#include "common.h"
#include <stdlib.h>
#include "syntax.h"
@@ -28,6 +41,8 @@
#ifdef ERROR_RESILIENCE
+//#define PRINT_RVLC
+
uint8_t rvlc_scale_factor_data(ic_stream *ics, bitfile *ld)
{uint8_t bits = 9;
@@ -73,10 +88,11 @@
uint8_t rvlc_decode_scale_factors(ic_stream *ics, bitfile *ld)
{uint8_t result;
+ uint8_t intensity_used = 0;
uint8_t *rvlc_sf_buffer = NULL;
uint8_t *rvlc_esc_buffer = NULL;
- bitfile ld_rvlc_sf;
- bitfile ld_rvlc_esc;
+ bitfile ld_rvlc_sf, ld_rvlc_esc;
+// bitfile ld_rvlc_sf_rev, ld_rvlc_esc_rev;
if (ics->length_of_rvlc_sf > 0)
{@@ -87,6 +103,8 @@
DEBUGVAR(1,156,"rvlc_decode_scale_factors(): bitbuffer: length_of_rvlc_sf"));
faad_initbits(&ld_rvlc_sf, (void*)rvlc_sf_buffer);
+// faad_initbits_rev(&ld_rvlc_sf_rev, (void*)rvlc_sf_buffer,
+// ics->length_of_rvlc_sf);
}
if (ics->sf_escapes_present)
@@ -98,10 +116,15 @@
DEBUGVAR(1,157,"rvlc_decode_scale_factors(): bitbuffer: length_of_rvlc_escapes"));
faad_initbits(&ld_rvlc_esc, (void*)rvlc_esc_buffer);
+// faad_initbits_rev(&ld_rvlc_esc_rev, (void*)rvlc_esc_buffer,
+// ics->length_of_rvlc_escapes);
}
/* decode the rvlc scale factors and escapes */
- result = rvlc_decode_sf_forward(ics, &ld_rvlc_sf, &ld_rvlc_esc);
+ result = rvlc_decode_sf_forward(ics, &ld_rvlc_sf,
+ &ld_rvlc_esc, &intensity_used);
+// result = rvlc_decode_sf_reverse(ics, &ld_rvlc_sf_rev,
+// &ld_rvlc_esc_rev, intensity_used);
if (rvlc_esc_buffer) free(rvlc_esc_buffer);
@@ -110,9 +133,10 @@
return result;
}
-static uint8_t rvlc_decode_sf_forward(ic_stream *ics, bitfile *ld_sf, bitfile *ld_esc)
+static uint8_t rvlc_decode_sf_forward(ic_stream *ics, bitfile *ld_sf, bitfile *ld_esc,
+ uint8_t *intensity_used)
{- uint8_t g, sfb;
+ int8_t g, sfb;
int8_t t = 0;
int8_t error = 0;
int8_t noise_pcm_flag = 1;
@@ -121,7 +145,7 @@
int16_t is_position = 0;
int16_t noise_energy = ics->global_gain - 90 - 256;
-#if 0
+#ifdef PRINT_RVLC
printf("\nglobal_gain: %d\n", ics->global_gain);#endif
@@ -141,8 +165,10 @@
case INTENSITY_HCB: /* intensity books */
case INTENSITY_HCB2:
+ *intensity_used = 1;
+
/* decode intensity position */
- t = rvlc_huffman_sf(ld_sf, ld_esc);
+ t = rvlc_huffman_sf(ld_sf, ld_esc, +1);
is_position += t;
ics->scale_factors[g][sfb] = is_position;
@@ -157,7 +183,7 @@
noise_pcm_flag = 0;
noise_energy += n;
} else {- t = rvlc_huffman_sf(ld_sf, ld_esc);
+ t = rvlc_huffman_sf(ld_sf, ld_esc, +1);
noise_energy += t;
}
@@ -169,7 +195,7 @@
default: /* spectral books */
/* decode scale factor */
- t = rvlc_huffman_sf(ld_sf, ld_esc);
+ t = rvlc_huffman_sf(ld_sf, ld_esc, +1);
scale_factor += t;
if (scale_factor < 0)
@@ -179,7 +205,7 @@
break;
}
-#if 0
+#ifdef PRINT_RVLC
printf("%3d:%4d%4d\n", sfb, ics->sfb_cb[g][sfb],ics->scale_factors[g][sfb]);
#endif
@@ -190,7 +216,7 @@
}
}
}
-#if 0
+#ifdef PRINT_RVLC
printf("\n\n");#endif
@@ -197,6 +223,114 @@
return 0;
}
+static uint8_t rvlc_decode_sf_reverse(ic_stream *ics, bitfile *ld_sf, bitfile *ld_esc,
+ uint8_t intensity_used)
+{+ int8_t g, sfb;
+ int8_t t = 0;
+ int8_t error = 0;
+ int8_t noise_pcm_flag = 1, is_pcm_flag = 1, sf_pcm_flag = 1;
+
+ int16_t scale_factor = ics->rev_global_gain;
+ int16_t is_position = 0;
+ int16_t noise_energy = ics->rev_global_gain;
+
+#ifdef PRINT_RVLC
+ printf("\nrev_global_gain: %d\n", ics->rev_global_gain);+#endif
+
+ if (intensity_used)
+ {+ is_position = rvlc_huffman_sf(ld_sf, ld_esc, -1);
+#ifdef PRINT_RVLC
+ printf("is_position: %d\n", is_position);+#endif
+ }
+
+ for (g = ics->num_window_groups-1; g >= 0; g--)
+ {+ for (sfb = ics->max_sfb-1; sfb >= 0; sfb--)
+ {+ if (error)
+ {+ ics->scale_factors[g][sfb] = 0;
+ } else {+ switch (ics->sfb_cb[g][sfb])
+ {+ case ZERO_HCB: /* zero book */
+ ics->scale_factors[g][sfb] = 0;
+ break;
+ case INTENSITY_HCB: /* intensity books */
+ case INTENSITY_HCB2:
+
+ if (is_pcm_flag)
+ {+ is_pcm_flag = 0;
+ ics->scale_factors[g][sfb] = is_position;
+ } else {+ t = rvlc_huffman_sf(ld_sf, ld_esc, -1);
+ is_position -= t;
+
+ ics->scale_factors[g][sfb] = is_position;
+ }
+
+ break;
+ case NOISE_HCB: /* noise books */
+
+ /* decode noise energy */
+ if (noise_pcm_flag)
+ {+ noise_pcm_flag = 0;
+ noise_energy = ics->dpcm_noise_last_position;
+ } else {+ t = rvlc_huffman_sf(ld_sf, ld_esc, -1);
+ noise_energy -= t;
+ }
+
+ ics->scale_factors[g][sfb] = noise_energy;
+
+ break;
+ case BOOKSCL: /* invalid books */
+ return 3;
+ default: /* spectral books */
+
+ if (sf_pcm_flag || (sfb == 0))
+ {+ sf_pcm_flag = 0;
+ if (sfb == 0)
+ scale_factor = ics->global_gain;
+ } else {+ /* decode scale factor */
+ t = rvlc_huffman_sf(ld_sf, ld_esc, -1);
+ scale_factor -= t;
+ }
+
+ ics->scale_factors[g][sfb] = scale_factor;
+
+ if (scale_factor < 0)
+ return 4;
+
+ break;
+ }
+#ifdef PRINT_RVLC
+ printf("%3d:%4d%4d\n", sfb, ics->sfb_cb[g][sfb],+ ics->scale_factors[g][sfb]);
+#endif
+ if (t == 99)
+ {+ error = 1;
+ }
+ }
+ }
+ }
+
+#ifdef PRINT_RVLC
+ printf("\n\n");+#endif
+
+ return 0;
+}
+
/* index == 99 means not allowed codeword */
static rvlc_huff_table book_rvlc[] = {/*index length codeword */
@@ -285,7 +419,8 @@
{ 99, 21, 0 } /* Shouldn't come this far */};
-static int8_t rvlc_huffman_sf(bitfile *ld_sf, bitfile *ld_esc)
+static int8_t rvlc_huffman_sf(bitfile *ld_sf, bitfile *ld_esc,
+ int8_t direction)
{uint8_t i, j;
int8_t index;
@@ -293,7 +428,10 @@
rvlc_huff_table *h = book_rvlc;
i = h->len;
- cw = faad_getbits(ld_sf, i);
+ if (direction > 0)
+ cw = faad_getbits(ld_sf, i);
+ else
+ cw = faad_getbits_rev(ld_sf, i);
while ((cw != h->cw)
&& (i < 10))
@@ -302,7 +440,10 @@
j = h->len-i;
i += j;
cw <<= j;
- cw |= faad_getbits(ld_sf, j);
+ if (direction > 0)
+ cw |= faad_getbits(ld_sf, j);
+ else
+ cw |= faad_getbits_rev(ld_sf, j);
}
index = h->index;
@@ -309,23 +450,30 @@
if (index == +ESC_VAL)
{- int8_t esc = rvlc_huffman_esc(ld_esc);
+ int8_t esc = rvlc_huffman_esc(ld_esc, direction);
if (esc == 99)
return 99;
index += esc;
+#ifdef PRINT_RVLC
+ printf("esc: %d - ", esc);+#endif
}
if (index == -ESC_VAL)
{- int8_t esc = rvlc_huffman_esc(ld_esc);
+ int8_t esc = rvlc_huffman_esc(ld_esc, direction);
if (esc == 99)
return 99;
index -= esc;
+#ifdef PRINT_RVLC
+ printf("esc: %d - ", esc);+#endif
}
return index;
}
-static int8_t rvlc_huffman_esc(bitfile *ld)
+static int8_t rvlc_huffman_esc(bitfile *ld,
+ int8_t direction)
{uint8_t i, j;
uint32_t cw;
@@ -332,7 +480,10 @@
rvlc_huff_table *h = book_escape;
i = h->len;
- cw = faad_getbits(ld, i);
+ if (direction > 0)
+ cw = faad_getbits(ld, i);
+ else
+ cw = faad_getbits_rev(ld, i);
while ((cw != h->cw)
&& (i < 21))
@@ -341,7 +492,10 @@
j = h->len-i;
i += j;
cw <<= j;
- cw |= faad_getbits(ld, j);
+ if (direction > 0)
+ cw |= faad_getbits(ld, j);
+ else
+ cw |= faad_getbits_rev(ld, j);
}
return h->index;
--- a/libfaad/rvlc_scale_factors.h
+++ b/libfaad/rvlc_scale_factors.h
@@ -16,7 +16,7 @@
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
**
-** $Id: rvlc_scale_factors.h,v 1.2 2002/08/07 08:14:31 menno Exp $
+** $Id: rvlc_scale_factors.h,v 1.3 2002/09/29 10:34:00 menno Exp $
**/
#ifndef __RVLC_SCF_H__
@@ -42,10 +42,15 @@
static uint8_t rvlc_decode_sf_forward(ic_stream *ics,
bitfile *ld_sf,
- bitfile *ld_esc);
-static int8_t rvlc_huffman_sf(bitfile *ld_sf,
- bitfile *ld_esc);
-static int8_t rvlc_huffman_esc(bitfile *ld_esc);
+ bitfile *ld_esc,
+ uint8_t *is_used);
+static uint8_t rvlc_decode_sf_reverse(ic_stream *ics,
+ bitfile *ld_sf,
+ bitfile *ld_esc,
+ uint8_t is_used);
+static int8_t rvlc_huffman_sf(bitfile *ld_sf, bitfile *ld_esc,
+ int8_t direction);
+static int8_t rvlc_huffman_esc(bitfile *ld_esc, int8_t direction);
#ifdef __cplusplus