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authorRamiro Polla <ramiro.polla@gmail.com>2008-08-19 16:07:58 +0000
committerRamiro Polla <ramiro.polla@gmail.com>2008-08-19 16:07:58 +0000
commit0d962ecb703be23fd4cf2894a4aba9b2eb13dfbf (patch)
tree59576b0e35b560a9ab0474bbc82328c04af987b1 /libavcodec/alacenc.c
parentc89cb5894e63d6d2698a8e1d12f8533823ed2c2f (diff)
downloadffmpeg-0d962ecb703be23fd4cf2894a4aba9b2eb13dfbf.tar.gz
Import more OKed parts of ALAC encoder from GSoC repo.
Originally committed as revision 14843 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/alacenc.c')
-rw-r--r--libavcodec/alacenc.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/libavcodec/alacenc.c b/libavcodec/alacenc.c
index 0a802f1525..f18ab2634b 100644
--- a/libavcodec/alacenc.c
+++ b/libavcodec/alacenc.c
@@ -38,6 +38,11 @@
#define ALAC_MAX_LPC_PRECISION 9
#define ALAC_MAX_LPC_SHIFT 9
+#define ALAC_CHMODE_LEFT_RIGHT 0
+#define ALAC_CHMODE_LEFT_SIDE 1
+#define ALAC_CHMODE_RIGHT_SIDE 2
+#define ALAC_CHMODE_MID_SIDE 3
+
typedef struct RiceContext {
int history_mult;
int initial_history;
@@ -53,9 +58,12 @@ typedef struct LPCContext {
typedef struct AlacEncodeContext {
int compression_level;
+ int min_prediction_order;
+ int max_prediction_order;
int max_coded_frame_size;
int write_sample_size;
int32_t sample_buf[MAX_CHANNELS][DEFAULT_FRAME_SIZE];
+ int32_t predictor_buf[DEFAULT_FRAME_SIZE];
int interlacing_shift;
int interlacing_leftweight;
PutBitContext pbctx;
@@ -116,6 +124,20 @@ static void write_frame_header(AlacEncodeContext *s, int is_verbatim)
put_bits(&s->pbctx, 32, s->avctx->frame_size); // No. of samples in the frame
}
+static void calc_predictor_params(AlacEncodeContext *s, int ch)
+{
+ int32_t coefs[MAX_LPC_ORDER][MAX_LPC_ORDER];
+ int shift[MAX_LPC_ORDER];
+ int opt_order;
+
+ opt_order = ff_lpc_calc_coefs(&s->dspctx, s->sample_buf[ch], s->avctx->frame_size, DEFAULT_MIN_PRED_ORDER, DEFAULT_MAX_PRED_ORDER,
+ ALAC_MAX_LPC_PRECISION, coefs, shift, 1, ORDER_METHOD_EST, ALAC_MAX_LPC_SHIFT, 1);
+
+ s->lpc[ch].lpc_order = opt_order;
+ s->lpc[ch].lpc_quant = shift[opt_order-1];
+ memcpy(s->lpc[ch].lpc_coeff, coefs[opt_order-1], opt_order*sizeof(int));
+}
+
static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n)
{
int i, best;
@@ -147,6 +169,53 @@ static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n)
best = i;
}
}
+ return best;
+}
+
+static void alac_stereo_decorrelation(AlacEncodeContext *s)
+{
+ int32_t *left = s->sample_buf[0], *right = s->sample_buf[1];
+ int i, mode, n = s->avctx->frame_size;
+ int32_t tmp;
+
+ mode = estimate_stereo_mode(left, right, n);
+
+ switch(mode)
+ {
+ case ALAC_CHMODE_LEFT_RIGHT:
+ s->interlacing_leftweight = 0;
+ s->interlacing_shift = 0;
+ break;
+
+ case ALAC_CHMODE_LEFT_SIDE:
+ for(i=0; i<n; i++) {
+ right[i] = left[i] - right[i];
+ }
+ s->interlacing_leftweight = 1;
+ s->interlacing_shift = 0;
+ break;
+
+ case ALAC_CHMODE_RIGHT_SIDE:
+ for(i=0; i<n; i++) {
+ tmp = right[i];
+ right[i] = left[i] - right[i];
+ left[i] = tmp + (right[i] >> 31);
+ }
+ s->interlacing_leftweight = 1;
+ s->interlacing_shift = 31;
+ break;
+
+ default:
+ for(i=0; i<n; i++) {
+ tmp = left[i];
+ left[i] = (tmp + right[i]) >> 1;
+ right[i] = tmp - right[i];
+ }
+ s->interlacing_leftweight = 1;
+ s->interlacing_shift = 1;
+ break;
+ }
+}
static void write_compressed_frame(AlacEncodeContext *s)
{
@@ -226,6 +295,32 @@ static av_cold int alac_encode_init(AVCodecContext *avctx)
AV_WB8(alac_extradata+20, s->rc.k_modifier);
}
+ if(avctx->min_prediction_order >= 0) {
+ if(avctx->min_prediction_order < MIN_LPC_ORDER ||
+ avctx->min_prediction_order > MAX_LPC_ORDER) {
+ av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n", avctx->min_prediction_order);
+ return -1;
+ }
+
+ s->min_prediction_order = avctx->min_prediction_order;
+ }
+
+ if(avctx->max_prediction_order >= 0) {
+ if(avctx->max_prediction_order < MIN_LPC_ORDER ||
+ avctx->max_prediction_order > MAX_LPC_ORDER) {
+ av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n", avctx->max_prediction_order);
+ return -1;
+ }
+
+ s->max_prediction_order = avctx->max_prediction_order;
+ }
+
+ if(s->max_prediction_order < s->min_prediction_order) {
+ av_log(avctx, AV_LOG_ERROR, "invalid prediction orders: min=%d max=%d\n",
+ s->min_prediction_order, s->max_prediction_order);
+ return -1;
+ }
+
avctx->extradata = alac_extradata;
avctx->extradata_size = ALAC_EXTRADATA_SIZE;
@@ -255,6 +350,9 @@ static int alac_encode_frame(AVCodecContext *avctx, uint8_t *frame,
return -1;
}
+verbatim:
+ init_put_bits(pb, frame, buf_size);
+
if((s->compression_level == 0) || verbatim_flag) {
// Verbatim mode
int16_t *samples = data;