[FFmpeg-cvslog] lavc/flac: Fix encoding and decoding with high lpc.
Carl Eugen Hoyos
git at videolan.org
Sun May 17 03:05:02 CEST 2015
ffmpeg | branch: master | Carl Eugen Hoyos <cehoyos at ag.or.at> | Tue May 12 13:00:29 2015 +0200| [e609cfd697f8eed7325591f767585041719807d1] | committer: Carl Eugen Hoyos
lavc/flac: Fix encoding and decoding with high lpc.
Based on an analysis by trac user lvqcl.
Fixes ticket #4421, reported by Chase Walker.
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e609cfd697f8eed7325591f767585041719807d1
---
doc/decoders.texi | 17 +++++++++++++++++
libavcodec/arm/flacdsp_init_arm.c | 4 ++--
libavcodec/flacdec.c | 24 +++++++++++++++++++++++-
libavcodec/flacdsp.c | 11 ++++-------
libavcodec/flacdsp.h | 12 ++++++++----
libavcodec/flacenc.c | 27 ++++++++++++++++++++++-----
libavcodec/version.h | 2 +-
libavcodec/x86/flacdsp_init.c | 10 ++++------
8 files changed, 81 insertions(+), 26 deletions(-)
diff --git a/doc/decoders.texi b/doc/decoders.texi
index 01fca9f..68196cf 100644
--- a/doc/decoders.texi
+++ b/doc/decoders.texi
@@ -83,6 +83,23 @@ Loud sounds are fully compressed. Soft sounds are enhanced.
@end table
+ at section flac
+
+FLAC audio decoder.
+
+This decoder aims to implement the complete FLAC specification from Xiph.
+
+ at subsection FLAC Decoder options
+
+ at table @option
+
+ at item -use_buggy_lpc
+The lavc FLAC encoder used to produce buggy streams with high lpc values
+(like the default value). This option allows to decode such streams
+correctly by using lavc's old buggy lpc logic for decoding.
+
+ at end table
+
@section ffwavesynth
Internal wave synthetizer.
diff --git a/libavcodec/arm/flacdsp_init_arm.c b/libavcodec/arm/flacdsp_init_arm.c
index 82a807f..564e3dc 100644
--- a/libavcodec/arm/flacdsp_init_arm.c
+++ b/libavcodec/arm/flacdsp_init_arm.c
@@ -27,6 +27,6 @@ void ff_flac_lpc_16_arm(int32_t *samples, const int coeffs[32], int order,
av_cold void ff_flacdsp_init_arm(FLACDSPContext *c, enum AVSampleFormat fmt, int channels,
int bps)
{
- if (CONFIG_FLAC_DECODER && bps <= 16)
- c->lpc = ff_flac_lpc_16_arm;
+ if (CONFIG_FLAC_DECODER)
+ c->lpc16 = ff_flac_lpc_16_arm;
}
diff --git a/libavcodec/flacdec.c b/libavcodec/flacdec.c
index 00b4726..36d2928 100644
--- a/libavcodec/flacdec.c
+++ b/libavcodec/flacdec.c
@@ -35,6 +35,7 @@
#include "libavutil/avassert.h"
#include "libavutil/crc.h"
+#include "libavutil/opt.h"
#include "avcodec.h"
#include "internal.h"
#include "get_bits.h"
@@ -48,6 +49,7 @@
typedef struct FLACContext {
+ AVClass *class;
struct FLACStreaminfo flac_stream_info;
AVCodecContext *avctx; ///< parent AVCodecContext
@@ -61,6 +63,7 @@ typedef struct FLACContext {
int32_t *decoded[FLAC_MAX_CHANNELS]; ///< decoded samples
uint8_t *decoded_buffer;
unsigned int decoded_buffer_size;
+ int buggy_lpc; ///< use workaround for old lavc encoded files
FLACDSPContext dsp;
} FLACContext;
@@ -343,7 +346,13 @@ static int decode_subframe_lpc(FLACContext *s, int32_t *decoded, int pred_order,
if ((ret = decode_residuals(s, decoded, pred_order)) < 0)
return ret;
- s->dsp.lpc(decoded, coeffs, pred_order, qlevel, s->blocksize);
+ if ( ( s->buggy_lpc && s->flac_stream_info.bps <= 16)
+ || ( !s->buggy_lpc && bps <= 16
+ && bps + coeff_prec + av_log2(pred_order) <= 32)) {
+ s->dsp.lpc16(decoded, coeffs, pred_order, qlevel, s->blocksize);
+ } else {
+ s->dsp.lpc32(decoded, coeffs, pred_order, qlevel, s->blocksize);
+ }
return 0;
}
@@ -605,6 +614,18 @@ static av_cold int flac_decode_close(AVCodecContext *avctx)
return 0;
}
+static const AVOption options[] = {
+{ "use_buggy_lpc", "emulate old buggy lavc behavior", offsetof(FLACContext, buggy_lpc), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM },
+{ NULL },
+};
+
+static const AVClass flac_decoder_class = {
+ "FLAC decoder",
+ av_default_item_name,
+ options,
+ LIBAVUTIL_VERSION_INT,
+};
+
AVCodec ff_flac_decoder = {
.name = "flac",
.long_name = NULL_IF_CONFIG_SMALL("FLAC (Free Lossless Audio Codec)"),
@@ -621,4 +642,5 @@ AVCodec ff_flac_decoder = {
AV_SAMPLE_FMT_S32,
AV_SAMPLE_FMT_S32P,
AV_SAMPLE_FMT_NONE },
+ .priv_class = &flac_decoder_class,
};
diff --git a/libavcodec/flacdsp.c b/libavcodec/flacdsp.c
index a83eb83..30b6648 100644
--- a/libavcodec/flacdsp.c
+++ b/libavcodec/flacdsp.c
@@ -88,13 +88,10 @@ static void flac_lpc_32_c(int32_t *decoded, const int coeffs[32],
av_cold void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt, int channels,
int bps)
{
- if (bps > 16) {
- c->lpc = flac_lpc_32_c;
- c->lpc_encode = flac_lpc_encode_c_32;
- } else {
- c->lpc = flac_lpc_16_c;
- c->lpc_encode = flac_lpc_encode_c_16;
- }
+ c->lpc16 = flac_lpc_16_c;
+ c->lpc32 = flac_lpc_32_c;
+ c->lpc16_encode = flac_lpc_encode_c_16;
+ c->lpc32_encode = flac_lpc_encode_c_32;
switch (fmt) {
case AV_SAMPLE_FMT_S32:
diff --git a/libavcodec/flacdsp.h b/libavcodec/flacdsp.h
index 417381c..f5cbd94 100644
--- a/libavcodec/flacdsp.h
+++ b/libavcodec/flacdsp.h
@@ -25,10 +25,14 @@
typedef struct FLACDSPContext {
void (*decorrelate[4])(uint8_t **out, int32_t **in, int channels,
int len, int shift);
- void (*lpc)(int32_t *samples, const int coeffs[32], int order,
- int qlevel, int len);
- void (*lpc_encode)(int32_t *res, const int32_t *smp, int len, int order,
- const int32_t coefs[32], int shift);
+ void (*lpc16)(int32_t *samples, const int coeffs[32], int order,
+ int qlevel, int len);
+ void (*lpc32)(int32_t *samples, const int coeffs[32], int order,
+ int qlevel, int len);
+ void (*lpc16_encode)(int32_t *res, const int32_t *smp, int len, int order,
+ const int32_t coefs[32], int shift);
+ void (*lpc32_encode)(int32_t *res, const int32_t *smp, int len, int order,
+ const int32_t coefs[32], int shift);
} FLACDSPContext;
void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt, int channels, int bps);
diff --git a/libavcodec/flacenc.c b/libavcodec/flacenc.c
index bc6d00a..b6dc4d5 100644
--- a/libavcodec/flacenc.c
+++ b/libavcodec/flacenc.c
@@ -838,8 +838,13 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
order = av_clip(order, min_order - 1, max_order - 1);
if (order == last_order)
continue;
- s->flac_dsp.lpc_encode(res, smp, n, order+1, coefs[order],
- shift[order]);
+ if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(order) <= 32) {
+ s->flac_dsp.lpc16_encode(res, smp, n, order+1, coefs[order],
+ shift[order]);
+ } else {
+ s->flac_dsp.lpc32_encode(res, smp, n, order+1, coefs[order],
+ shift[order]);
+ }
bits[i] = find_subframe_rice_params(s, sub, order+1);
if (bits[i] < bits[opt_index]) {
opt_index = i;
@@ -853,7 +858,11 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
opt_order = 0;
bits[0] = UINT32_MAX;
for (i = min_order-1; i < max_order; i++) {
- s->flac_dsp.lpc_encode(res, smp, n, i+1, coefs[i], shift[i]);
+ if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(i) <= 32) {
+ s->flac_dsp.lpc16_encode(res, smp, n, i+1, coefs[i], shift[i]);
+ } else {
+ s->flac_dsp.lpc32_encode(res, smp, n, i+1, coefs[i], shift[i]);
+ }
bits[i] = find_subframe_rice_params(s, sub, i+1);
if (bits[i] < bits[opt_order])
opt_order = i;
@@ -871,7 +880,11 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
for (i = last-step; i <= last+step; i += step) {
if (i < min_order-1 || i >= max_order || bits[i] < UINT32_MAX)
continue;
- s->flac_dsp.lpc_encode(res, smp, n, i+1, coefs[i], shift[i]);
+ if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(i) <= 32) {
+ s->flac_dsp.lpc32_encode(res, smp, n, i+1, coefs[i], shift[i]);
+ } else {
+ s->flac_dsp.lpc16_encode(res, smp, n, i+1, coefs[i], shift[i]);
+ }
bits[i] = find_subframe_rice_params(s, sub, i+1);
if (bits[i] < bits[opt_order])
opt_order = i;
@@ -886,7 +899,11 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
for (i = 0; i < sub->order; i++)
sub->coefs[i] = coefs[sub->order-1][i];
- s->flac_dsp.lpc_encode(res, smp, n, sub->order, sub->coefs, sub->shift);
+ if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(opt_order) <= 32) {
+ s->flac_dsp.lpc16_encode(res, smp, n, sub->order, sub->coefs, sub->shift);
+ } else {
+ s->flac_dsp.lpc32_encode(res, smp, n, sub->order, sub->coefs, sub->shift);
+ }
find_subframe_rice_params(s, sub, sub->order);
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 8679ac6..dd47af0 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -30,7 +30,7 @@
#define LIBAVCODEC_VERSION_MAJOR 56
#define LIBAVCODEC_VERSION_MINOR 39
-#define LIBAVCODEC_VERSION_MICRO 100
+#define LIBAVCODEC_VERSION_MICRO 101
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
LIBAVCODEC_VERSION_MINOR, \
diff --git a/libavcodec/x86/flacdsp_init.c b/libavcodec/x86/flacdsp_init.c
index d04af45..e28c5c9 100644
--- a/libavcodec/x86/flacdsp_init.c
+++ b/libavcodec/x86/flacdsp_init.c
@@ -85,8 +85,7 @@ av_cold void ff_flacdsp_init_x86(FLACDSPContext *c, enum AVSampleFormat fmt, int
}
}
if (EXTERNAL_SSE4(cpu_flags)) {
- if (bps > 16)
- c->lpc = ff_flac_lpc_32_sse4;
+ c->lpc32 = ff_flac_lpc_32_sse4;
}
if (EXTERNAL_AVX(cpu_flags)) {
if (fmt == AV_SAMPLE_FMT_S16) {
@@ -102,15 +101,14 @@ av_cold void ff_flacdsp_init_x86(FLACDSPContext *c, enum AVSampleFormat fmt, int
}
}
if (EXTERNAL_XOP(cpu_flags)) {
- if (bps > 16)
- c->lpc = ff_flac_lpc_32_xop;
+ c->lpc32 = ff_flac_lpc_32_xop;
}
#endif
#if CONFIG_FLAC_ENCODER
if (EXTERNAL_SSE4(cpu_flags)) {
- if (CONFIG_GPL && bps == 16)
- c->lpc_encode = ff_flac_enc_lpc_16_sse4;
+ if (CONFIG_GPL)
+ c->lpc16_encode = ff_flac_enc_lpc_16_sse4;
}
#endif
#endif /* HAVE_YASM */
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