wma encoder

Originally committed as revision 7855 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 402 insertions, 0 deletions

diff --git a/libavcodec/wmaenc.c b/libavcodec/wmaenc.c
new file mode 100644
index 0000000000..c09ba4d679
--- /dev/null
+++ b/libavcodec/wmaenc.c
@@ -0,0 +1,402 @@
+/*
+ * WMA compatible encoder
+ * Copyright (c) 2007 Michael Niedermayer
+ *
+ * This file is part of FFmpeg.
+ *
+ * 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.
+ *
+ * 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avcodec.h"
+#include "wma.h"
+
+#undef NDEBUG
+#include <assert.h>
+
+
+static int encode_init(AVCodecContext * avctx){
+    WMADecodeContext *s = avctx->priv_data;
+    int i, flags1, flags2;
+    uint8_t *extradata;
+
+    if(avctx->channels > MAX_CHANNELS)
+        return -1;
+
+    /* extract flag infos */
+    flags1 = 0;
+    flags2 = 1;
+    if (avctx->codec->id == CODEC_ID_WMAV1) {
+        extradata= av_malloc(4);
+        avctx->extradata_size= 4;
+        extradata[0] = flags1;
+        extradata[1] = flags1>>8;
+        extradata[2] = flags2;
+        extradata[3] = flags2>>8;
+    } else if (avctx->codec->id == CODEC_ID_WMAV2) {
+        extradata= av_mallocz(10);
+        avctx->extradata_size= 10;
+        extradata[0] = flags1;
+        extradata[1] = flags1>>8;
+        extradata[2] = flags1>>16;
+        extradata[3] = flags1>>24;
+        extradata[4] = flags2;
+        extradata[5] = flags2>>8;
+    }else
+        assert(0);
+    avctx->extradata= extradata;
+    s->use_exp_vlc = flags2 & 0x0001;
+    s->use_bit_reservoir = flags2 & 0x0002;
+    s->use_variable_block_len = flags2 & 0x0004;
+
+    ff_wma_init(avctx, flags2);
+
+    /* init MDCT */
+    for(i = 0; i < s->nb_block_sizes; i++)
+        ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 0);
+
+    avctx->block_align=
+    s->block_align= avctx->bit_rate*(int64_t)s->frame_len / (avctx->sample_rate*8);
+//av_log(NULL, AV_LOG_ERROR, "%d %d %d %d\n", s->block_align, avctx->bit_rate, s->frame_len, avctx->sample_rate);
+    avctx->frame_size= s->frame_len;
+
+    return 0;
+}
+
+
+static void apply_window_and_mdct(AVCodecContext * avctx, signed short * audio, int len) {
+    WMADecodeContext *s = avctx->priv_data;
+    int window_index= s->frame_len_bits - s->block_len_bits;
+    int i, j, channel;
+    const float * win = s->windows[window_index];
+    int window_len = 1 << s->block_len_bits;
+    float n = window_len/2;
+
+    for (channel = 0; channel < avctx->channels; channel++) {
+        memcpy(s->output, s->frame_out[channel], sizeof(float)*window_len);
+        j = channel;
+        for (i = 0; i < len; i++, j += avctx->channels){
+            s->output[i+window_len]  = audio[j] / n * win[i];
+            s->frame_out[channel][i] = audio[j] / n * win[window_len - i - 1];
+        }
+        ff_mdct_calc(&s->mdct_ctx[window_index], s->coefs[channel], s->output, s->mdct_tmp);
+    }
+}
+
+//FIXME use for decoding too
+static void init_exp(WMADecodeContext *s, int ch, int *exp_param){
+    int n;
+    const uint16_t *ptr;
+    float v, *q, max_scale, *q_end;
+
+    ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
+    q = s->exponents[ch];
+    q_end = q + s->block_len;
+    max_scale = 0;
+    while (q < q_end) {
+        /* XXX: use a table */
+        v = pow(10, *exp_param++ * (1.0 / 16.0));
+        max_scale= FFMAX(max_scale, v);
+        n = *ptr++;
+        do {
+            *q++ = v;
+        } while (--n);
+    }
+    s->max_exponent[ch] = max_scale;
+}
+
+static void encode_exp_vlc(WMADecodeContext *s, int ch, const int *exp_param){
+    int last_exp;
+    const uint16_t *ptr;
+    float *q, *q_end;
+
+    ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
+    q = s->exponents[ch];
+    q_end = q + s->block_len;
+    if (s->version == 1) {
+        last_exp= *exp_param++;
+        assert(last_exp-10 >= 0 && last_exp-10 < 32);
+        put_bits(&s->pb, 5, last_exp - 10);
+        q+= *ptr++;
+    }else
+        last_exp = 36;
+    while (q < q_end) {
+        int exp = *exp_param++;
+        int code = exp - last_exp + 60;
+        assert(code >= 0 && code < 120);
+        put_bits(&s->pb, ff_wma_scale_huffbits[code], ff_wma_scale_huffcodes[code]);
+        /* XXX: use a table */
+        q+= *ptr++;
+        last_exp= exp;
+    }
+}
+
+static int encode_block(WMADecodeContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], int total_gain){
+    int v, bsize, ch, coef_nb_bits, parse_exponents;
+    float mdct_norm;
+    int nb_coefs[MAX_CHANNELS];
+    static const int fixed_exp[25]={20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20};
+
+    //FIXME remove duplication relative to decoder
+    if (s->use_variable_block_len) {
+        assert(0); //FIXME not implemented
+    }else{
+        /* fixed block len */
+        s->next_block_len_bits = s->frame_len_bits;
+        s->prev_block_len_bits = s->frame_len_bits;
+        s->block_len_bits = s->frame_len_bits;
+    }
+
+    s->block_len = 1 << s->block_len_bits;
+//     assert((s->block_pos + s->block_len) <= s->frame_len);
+    bsize = s->frame_len_bits - s->block_len_bits;
+
+    //FIXME factor
+    v = s->coefs_end[bsize] - s->coefs_start;
+    for(ch = 0; ch < s->nb_channels; ch++)
+        nb_coefs[ch] = v;
+    {
+        int n4 = s->block_len / 2;
+        mdct_norm = 1.0 / (float)n4;
+        if (s->version == 1) {
+            mdct_norm *= sqrt(n4);
+        }
+    }
+
+    if (s->nb_channels == 2) {
+        put_bits(&s->pb, 1, s->ms_stereo= 1);
+    }
+
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        if (s->channel_coded[ch]) {
+            init_exp(s, ch, fixed_exp);
+        }
+    }
+
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        if (s->channel_coded[ch]) {
+            int16_t *coefs1;
+            float *coefs, *exponents, mult;
+            int i, n;
+
+            coefs1 = s->coefs1[ch];
+            exponents = s->exponents[ch];
+            mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
+            mult *= mdct_norm;
+            coefs = src_coefs[ch];
+            if (s->use_noise_coding && 0) {
+                assert(0); //FIXME not implemented
+            } else {
+                coefs += s->coefs_start;
+                n = nb_coefs[ch];
+                for(i = 0;i < n; i++){
+                    double t= *coefs++ / (exponents[i] * mult);
+                    if(t<-32768 || t>32767)
+                        return -1;
+
+                    coefs1[i] = lrint(t);
+                }
+            }
+        }
+    }
+
+    v = 0;
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        int a = s->channel_coded[ch]=1; //FIXME
+        put_bits(&s->pb, 1, a);
+        v |= a;
+    }
+
+    if (!v)
+        return 1;
+
+    for(v= total_gain-1; v>=127; v-= 127)
+        put_bits(&s->pb, 7, 127);
+    put_bits(&s->pb, 7, v);
+
+    coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
+
+    if (s->use_noise_coding) {
+        for(ch = 0; ch < s->nb_channels; ch++) {
+            if (s->channel_coded[ch]) {
+                int i, n;
+                n = s->exponent_high_sizes[bsize];
+                for(i=0;i<n;i++) {
+                    put_bits(&s->pb, 1, s->high_band_coded[ch][i]= 0);
+                    if (0)
+                        nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
+                }
+            }
+        }
+    }
+
+    parse_exponents = 1;
+    if (s->block_len_bits != s->frame_len_bits) {
+        put_bits(&s->pb, 1, parse_exponents);
+    }
+
+    if (parse_exponents) {
+        for(ch = 0; ch < s->nb_channels; ch++) {
+            if (s->channel_coded[ch]) {
+                if (s->use_exp_vlc) {
+                    encode_exp_vlc(s, ch, fixed_exp);
+                } else {
+                    assert(0); //FIXME not implemented
+//                    encode_exp_lsp(s, ch);
+                }
+            }
+        }
+    } else {
+        assert(0); //FIXME not implemented
+    }
+
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        if (s->channel_coded[ch]) {
+            int run, tindex;
+            int16_t *ptr, *eptr;
+            tindex = (ch == 1 && s->ms_stereo);
+            ptr = &s->coefs1[ch][0];
+            eptr = ptr + nb_coefs[ch];
+
+            run=0;
+            for(;ptr < eptr; ptr++){
+                if(*ptr){
+                    int level= *ptr;
+                    int abs_level= FFABS(level);
+                    int code= 0;
+                    if(abs_level <= s->coef_vlcs[tindex]->max_level){
+                        if(run < s->coef_vlcs[tindex]->levels[abs_level-1])
+                            code= run + s->int_table[tindex][abs_level-1];
+                    }
+
+                    assert(code < s->coef_vlcs[tindex]->n);
+                    put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[code], s->coef_vlcs[tindex]->huffcodes[code]);
+
+                    if(code == 0){
+                        if(1<<coef_nb_bits <= abs_level)
+                            return -1;
+
+                        put_bits(&s->pb, coef_nb_bits, abs_level);
+                        put_bits(&s->pb, s->frame_len_bits, run);
+                    }
+                    put_bits(&s->pb, 1, level > 0);
+                    run=0;
+                }else{
+                    run++;
+                }
+            }
+            if(run)
+                put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[1], s->coef_vlcs[tindex]->huffcodes[1]);
+        }
+        if (s->version == 1 && s->nb_channels >= 2) {
+            align_put_bits(&s->pb);
+        }
+    }
+    return 0;
+}
+
+static int encode_frame(WMADecodeContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], uint8_t *buf, int buf_size, int total_gain){
+    init_put_bits(&s->pb, buf, buf_size);
+
+    if (s->use_bit_reservoir) {
+        assert(0);//FIXME not implemented
+    }else{
+        if(encode_block(s, src_coefs, total_gain) < 0)
+            return INT_MAX;
+    }
+
+    align_put_bits(&s->pb);
+
+    return put_bits_count(&s->pb)/8 - s->block_align;
+}
+
+static int encode_superframe(AVCodecContext *avctx,
+                            unsigned char *buf, int buf_size, void *data){
+    WMADecodeContext *s = avctx->priv_data;
+    short *samples = data;
+    int i, total_gain, best;
+
+    s->block_len_bits= s->frame_len_bits; //required by non variable block len
+    s->block_len = 1 << s->block_len_bits;
+
+    apply_window_and_mdct(avctx, samples, avctx->frame_size);
+
+    if (s->ms_stereo) {
+        float a, b;
+        int i;
+
+        for(i = 0; i < s->block_len; i++) {
+            a = s->coefs[0][i]*0.5;
+            b = s->coefs[1][i]*0.5;
+            s->coefs[0][i] = a + b;
+            s->coefs[1][i] = a - b;
+        }
+    }
+
+#if 1
+    total_gain= 128;
+    for(i=64; i; i>>=1){
+        int error= encode_frame(s, s->coefs, buf, buf_size, total_gain-i);
+        if(error<0)
+            total_gain-= i;
+    }
+#else
+    total_gain= 90;
+    best= encode_frame(s, s->coefs, buf, buf_size, total_gain);
+    for(i=32; i; i>>=1){
+        int scoreL= encode_frame(s, s->coefs, buf, buf_size, total_gain-i);
+        int scoreR= encode_frame(s, s->coefs, buf, buf_size, total_gain+i);
+        av_log(NULL, AV_LOG_ERROR, "%d %d %d (%d)\n", scoreL, best, scoreR, total_gain);
+        if(scoreL < FFMIN(best, scoreR)){
+            best = scoreL;
+            total_gain -= i;
+        }else if(scoreR < best){
+            best = scoreR;
+            total_gain += i;
+        }
+    }
+#endif
+
+    encode_frame(s, s->coefs, buf, buf_size, total_gain);
+    assert((put_bits_count(&s->pb) & 7) == 0);
+    i= s->block_align - (put_bits_count(&s->pb)+7)/8;
+    assert(i>=0);
+    while(i--)
+        put_bits(&s->pb, 8, 'N');
+
+    flush_put_bits(&s->pb);
+    return pbBufPtr(&s->pb) - s->pb.buf;
+}
+
+AVCodec wmav1_encoder =
+{
+    "wmav1",
+    CODEC_TYPE_AUDIO,
+    CODEC_ID_WMAV1,
+    sizeof(WMADecodeContext),
+    encode_init,
+    encode_superframe,
+    ff_wma_end,
+};
+
+AVCodec wmav2_encoder =
+{
+    "wmav2",
+    CODEC_TYPE_AUDIO,
+    CODEC_ID_WMAV2,
+    sizeof(WMADecodeContext),
+    encode_init,
+    encode_superframe,
+    ff_wma_end,
+};