* Common code between the AC-3 encoder and decoder
* Copyright (c) 2000, 2001, 2002 Fabrice Bellard
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#define AC3_CRITICAL_BANDS 50
#define AC3_MAX_CPL_BANDS 18
+#include "libavutil/opt.h"
+#include "avcodec.h"
#include "ac3tab.h"
/* exponent encoding strategy */
#define EXP_D25 2
#define EXP_D45 3
+/* pre-defined gain values */
+#define LEVEL_PLUS_3DB 1.4142135623730950
+#define LEVEL_PLUS_1POINT5DB 1.1892071150027209
+#define LEVEL_MINUS_1POINT5DB 0.8408964152537145
+#define LEVEL_MINUS_3DB 0.7071067811865476
+#define LEVEL_MINUS_4POINT5DB 0.5946035575013605
+#define LEVEL_MINUS_6DB 0.5000000000000000
+#define LEVEL_MINUS_9DB 0.3535533905932738
+#define LEVEL_ZERO 0.0000000000000000
+#define LEVEL_ONE 1.0000000000000000
+
/** Delta bit allocation strategy */
typedef enum {
DBA_REUSE = 0,
EAC3_FRAME_TYPE_RESERVED
} EAC3FrameType;
+/**
+ * Encoding Options used by AVOption.
+ */
+typedef struct AC3EncOptions {
+ /* AC-3 metadata options*/
+ int dialogue_level;
+ int bitstream_mode;
+ float center_mix_level;
+ float surround_mix_level;
+ int dolby_surround_mode;
+ int audio_production_info;
+ int mixing_level;
+ int room_type;
+ int copyright;
+ int original;
+ int extended_bsi_1;
+ int preferred_stereo_downmix;
+ float ltrt_center_mix_level;
+ float ltrt_surround_mix_level;
+ float loro_center_mix_level;
+ float loro_surround_mix_level;
+ int extended_bsi_2;
+ int dolby_surround_ex_mode;
+ int dolby_headphone_mode;
+ int ad_converter_type;
+
+ /* other encoding options */
+ int allow_per_frame_metadata;
+} AC3EncOptions;
+
+
void ff_ac3_common_init(void);
+extern const int64_t ff_ac3_channel_layouts[];
+extern const AVOption ff_ac3_options[];
+
+extern AVCodec ff_ac3_float_encoder;
+extern AVCodec ff_ac3_fixed_encoder;
+
/**
* Calculate the log power-spectral density of the input signal.
* This gives a rough estimate of signal power in the frequency domain by using
uint8_t *dba_lengths, uint8_t *dba_values,
int16_t *mask);
-/**
- * Calculate bit allocation pointers.
- * The SNR is the difference between the masking curve and the signal. AC-3
- * uses this value for each frequency bin to allocate bits. The snroffset
- * parameter is a global adjustment to the SNR for all bins.
- *
- * @param[in] mask masking curve
- * @param[in] psd signal power for each frequency bin
- * @param[in] start starting bin location
- * @param[in] end ending bin location
- * @param[in] snr_offset SNR adjustment
- * @param[in] floor noise floor
- * @param[in] bap_tab look-up table for bit allocation pointers
- * @param[out] bap bit allocation pointers
- */
-void ff_ac3_bit_alloc_calc_bap(int16_t *mask, int16_t *psd, int start, int end,
- int snr_offset, int floor,
- const uint8_t *bap_tab, uint8_t *bap);
-
#endif /* AVCODEC_AC3_H */