* audio encoder psychoacoustic model
* Copyright (C) 2008 Konstantin Shishkov
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav 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 FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/** maximum possible number of bands */
#define PSY_MAX_BANDS 128
+/** maximum number of channels */
+#define PSY_MAX_CHANS 20
/**
* single band psychoacoustic information
*/
-typedef struct FFPsyBand{
+typedef struct FFPsyBand {
int bits;
float energy;
float threshold;
float distortion;
float perceptual_weight;
-}FFPsyBand;
+} FFPsyBand;
+
+/**
+ * single channel psychoacoustic information
+ */
+typedef struct FFPsyChannel {
+ FFPsyBand psy_bands[PSY_MAX_BANDS]; ///< channel bands information
+ float entropy; ///< total PE for this channel
+} FFPsyChannel;
+
+/**
+ * psychoacoustic information for an arbitrary group of channels
+ */
+typedef struct FFPsyChannelGroup {
+ FFPsyChannel *ch[PSY_MAX_CHANS]; ///< pointers to the individual channels in the group
+ uint8_t num_ch; ///< number of channels in this group
+ uint8_t coupling[PSY_MAX_BANDS]; ///< allow coupling for this band in the group
+} FFPsyChannelGroup;
/**
* windowing related information
*/
-typedef struct FFPsyWindowInfo{
+typedef struct FFPsyWindowInfo {
int window_type[3]; ///< window type (short/long/transitional, etc.) - current, previous and next
int window_shape; ///< window shape (sine/KBD/whatever)
int num_windows; ///< number of windows in a frame
int grouping[8]; ///< window grouping (for e.g. AAC)
int *window_sizes; ///< sequence of window sizes inside one frame (for eg. WMA)
-}FFPsyWindowInfo;
+} FFPsyWindowInfo;
/**
* context used by psychoacoustic model
*/
-typedef struct FFPsyContext{
+typedef struct FFPsyContext {
AVCodecContext *avctx; ///< encoder context
const struct FFPsyModel *model; ///< encoder-specific model functions
- FFPsyBand *psy_bands; ///< frame bands information
+ FFPsyChannel *ch; ///< single channel information
+ FFPsyChannelGroup *group; ///< channel group information
+ int num_groups; ///< number of channel groups
uint8_t **bands; ///< scalefactor band sizes for possible frame sizes
int *num_bands; ///< number of scalefactor bands for possible frame sizes
int num_lens; ///< number of scalefactor band sets
+ struct {
+ int size; ///< size of the bitresevoir in bits
+ int bits; ///< number of bits used in the bitresevoir
+ } bitres;
+
void* model_priv_data; ///< psychoacoustic model implementation private data
-}FFPsyContext;
+} FFPsyContext;
/**
* codec-specific psychoacoustic model implementation
typedef struct FFPsyModel {
const char *name;
int (*init) (FFPsyContext *apc);
+
+ /**
+ * Suggest window sequence for channel.
+ *
+ * @param ctx model context
+ * @param audio samples for the current frame
+ * @param la lookahead samples (NULL when unavailable)
+ * @param channel number of channel element to analyze
+ * @param prev_type previous window type
+ *
+ * @return suggested window information in a structure
+ */
FFPsyWindowInfo (*window)(FFPsyContext *ctx, const int16_t *audio, const int16_t *la, int channel, int prev_type);
- void (*analyze)(FFPsyContext *ctx, int channel, const float *coeffs, FFPsyWindowInfo *wi);
+
+ /**
+ * Perform psychoacoustic analysis and set band info (threshold, energy) for a group of channels.
+ *
+ * @param ctx model context
+ * @param channel channel number of the first channel in the group to perform analysis on
+ * @param coeffs array of pointers to the transformed coefficients
+ * @param wi window information for the channels in the group
+ */
+ void (*analyze)(FFPsyContext *ctx, int channel, const float **coeffs, const FFPsyWindowInfo *wi);
+
void (*end) (FFPsyContext *apc);
-}FFPsyModel;
+} FFPsyModel;
/**
* Initialize psychoacoustic model.
* @param num_lens number of possible frame lengths
* @param bands scalefactor band lengths for all frame lengths
* @param num_bands number of scalefactor bands for all frame lengths
+ * @param num_groups number of channel groups
+ * @param group_map array with # of channels in group - 1, for each group
*
* @return zero if successful, a negative value if not
*/
-av_cold int ff_psy_init(FFPsyContext *ctx, AVCodecContext *avctx,
- int num_lens,
- const uint8_t **bands, const int* num_bands);
+av_cold int ff_psy_init(FFPsyContext *ctx, AVCodecContext *avctx, int num_lens,
+ const uint8_t **bands, const int* num_bands,
+ int num_groups, const uint8_t *group_map);
/**
- * Suggest window sequence for channel.
+ * Determine what group a channel belongs to.
*
- * @param ctx model context
- * @param audio samples for the current frame
- * @param la lookahead samples (NULL when unavailable)
- * @param channel number of channel element to analyze
- * @param prev_type previous window type
- *
- * @return suggested window information in a structure
- */
-FFPsyWindowInfo ff_psy_suggest_window(FFPsyContext *ctx,
- const int16_t *audio, const int16_t *la,
- int channel, int prev_type);
-
-
-/**
- * Perform psychoacoustic analysis and set band info (threshold, energy).
+ * @param ctx psymodel context
+ * @param channel channel to locate the group for
*
- * @param ctx model context
- * @param channel audio channel number
- * @param coeffs pointer to the transformed coefficients
- * @param wi window information
+ * @return pointer to the FFPsyChannelGroup this channel belongs to
*/
-void ff_psy_set_band_info(FFPsyContext *ctx, int channel, const float *coeffs,
- FFPsyWindowInfo *wi);
+FFPsyChannelGroup *ff_psy_find_group(FFPsyContext *ctx, int channel);
/**
* Cleanup model context at the end.
projects / ffmpeg / blobdiff