Traneptora/FFmpeg
1
Fork 0
forked from FFmpeg/FFmpeg
Code Pull requests Activity

avcodec/ac3enc: Remove disabled code for RealAudio variant of AC-3

Browse source 
Implicitly disabled by 4679a474f0.
Given that no one has ever complained about this, this commit
removes the now dead code.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This commit is contained in:
Andreas Rheinhardt 2024-04-07 15:45:12 +02:00
parent 27a830c1d8
commit fee093a570
4 changed files with 17 additions and 41 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
doc/encoders.texi
View file

@ -144,8 +144,7 @@ If this option is unspecified it is set to @samp{aac_low}.
AC-3 audio encoders.
These encoders implement part of ATSC A/52:2010 and ETSI TS 102 366, as well as
the undocumented RealAudio 3 (a.k.a. dnet).
These encoders implement part of ATSC A/52:2010 and ETSI TS 102 366.
The @var{ac3} encoder uses floating-point math, while the @var{ac3_fixed}
encoder only uses fixed-point integer math. This does not mean that one is

44
libavcodec/ac3enc.c
View file

@ -874,8 +874,8 @@ static av_cold void bit_alloc_init(AC3EncodeContext *s)
/* compute real values */
/* currently none of these values change during encoding, so we can just
set them once at initialization */
s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->bit_alloc.sr_shift;
s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->bit_alloc.sr_shift;
s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code];
s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code];
s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code];
s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code];
@ -1812,8 +1812,6 @@ static void dprint_options(AC3EncodeContext *s)
switch (s->bitstream_id) {
case 6: msg = "AC-3 (alt syntax)"; break;
case 8: msg = "AC-3 (standard)"; break;
case 9: msg = "AC-3 (dnet half-rate)"; break;
case 10: msg = "AC-3 (dnet quater-rate)"; break;
case 16: msg = "E-AC-3 (enhanced)"; break;
default: msg = "ERROR";
}
@ -2132,18 +2130,8 @@ int ff_ac3_validate_metadata(AC3EncodeContext *s)
}
/* set bitstream id for alternate bitstream syntax */
if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) {
if (s->bitstream_id > 8 && s->bitstream_id < 11) {
if (!s->warned_alternate_bitstream) {
av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is "
"not compatible with reduced samplerates. writing of "
"extended bitstream information will be disabled.\n");
s->warned_alternate_bitstream = 1;
}
} else {
s->bitstream_id = 6;
}
}
if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2))
s->bitstream_id = 6;
return 0;
}
@ -2233,23 +2221,19 @@ static av_cold void set_channel_info(AVCodecContext *avctx)
static av_cold int validate_options(AC3EncodeContext *s)
{
AVCodecContext *avctx = s->avctx;
int i, ret, max_sr;
int ret;
set_channel_info(avctx);
/* validate sample rate */
/* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a
decoder that supports half sample rate so we can validate that
the generated files are correct. */
max_sr = s->eac3 ? 2 : 8;
for (i = 0; i <= max_sr; i++) {
if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate)
for (int i = 0;; i++) {
if (ff_ac3_sample_rate_tab[i] == avctx->sample_rate) {
s->bit_alloc.sr_code = i;
break;
}
av_assert1(ff_ac3_sample_rate_tab[i] != 0);
}
s->sample_rate = avctx->sample_rate;
s->bit_alloc.sr_shift = i / 3;
s->bit_alloc.sr_code = i % 3;
s->bitstream_id = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift;
s->bitstream_id = s->eac3 ? 16 : 8;
/* select a default bit rate if not set by the user */
if (!avctx->bit_rate) {
@ -2297,7 +2281,7 @@ static av_cold int validate_options(AC3EncodeContext *s)
parameter selection */
min_br_code = -1;
min_br_dist = INT64_MAX;
for (i = 0; i < 19; i++) {
for (int i = 0; i < 19; i++) {
long long br_dist = llabs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
if (br_dist < min_br_dist) {
min_br_dist = br_dist;
@ -2313,8 +2297,8 @@ static av_cold int validate_options(AC3EncodeContext *s)
} else {
int best_br = 0, best_code = 0;
long long best_diff = INT64_MAX;
for (i = 0; i < 19; i++) {
int br = (ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift) * 1000;
for (int i = 0; i < 19; i++) {
int br = ff_ac3_bitrate_tab[i] * 1000;
long long diff = llabs(br - avctx->bit_rate);
if (diff < best_diff) {
best_br = br;

2
libavcodec/ac3enc.h
View file

@ -256,8 +256,6 @@ typedef struct AC3EncodeContext {
uint8_t *ref_bap [AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< bit allocation pointers (bap)
int ref_bap_set; ///< indicates if ref_bap pointers have been set
int warned_alternate_bitstream;
/* fixed vs. float function pointers */
int (*mdct_init)(struct AC3EncodeContext *s);

9
libavcodec/eac3enc.c
View file

@ -134,13 +134,8 @@ void ff_eac3_output_frame_header(AC3EncodeContext *s)
put_bits(&s->pb, 2, 0); /* stream type = independent */
put_bits(&s->pb, 3, 0); /* substream id = 0 */
put_bits(&s->pb, 11, (s->frame_size / 2) - 1); /* frame size */
if (s->bit_alloc.sr_shift) {
put_bits(&s->pb, 2, 0x3); /* fscod2 */
put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
} else {
put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
put_bits(&s->pb, 2, s->num_blks_code); /* number of blocks */
}
put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
put_bits(&s->pb, 2, s->num_blks_code); /* number of blocks */
put_bits(&s->pb, 3, s->channel_mode); /* audio coding mode */
put_bits(&s->pb, 1, s->lfe_on); /* LFE channel indicator */
put_bits(&s->pb, 5, s->bitstream_id); /* bitstream id (EAC3=16) */