]> git.sesse.net Git - ffmpeg/blobdiff - libavcodec/ac3enc.c
Fix VDPAU decoding for some H264 samples.
[ffmpeg] / libavcodec / ac3enc.c
index 4f153191a05f4d2f244d4c69eda5adaa8b7d8c86..749967fedbb8963310712eb3447e3c1a4cc83ff9 100644 (file)
 #include "ac3.h"
 #include "audioconvert.h"
 #include "fft.h"
-
 #include "ac3enc.h"
 #include "eac3enc.h"
 
 typedef struct AC3Mant {
-    uint16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
+    int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
     int mant1_cnt, mant2_cnt, mant4_cnt;    ///< mantissa counts for bap=1,2,4
 } AC3Mant;
 
@@ -68,46 +67,6 @@ static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS] = {
 };
 
 
-#define OFFSET(param) offsetof(AC3EncodeContext, options.param)
-#define AC3ENC_PARAM (AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
-
-#define AC3ENC_TYPE_AC3_FIXED   0
-#define AC3ENC_TYPE_AC3         1
-#define AC3ENC_TYPE_EAC3        2
-
-#if CONFIG_AC3ENC_FLOAT
-#define AC3ENC_TYPE AC3ENC_TYPE_AC3
-#include "ac3enc_opts_template.c"
-static AVClass ac3enc_class = { "AC-3 Encoder", av_default_item_name,
-                                ac3_options, LIBAVUTIL_VERSION_INT };
-#undef AC3ENC_TYPE
-#define AC3ENC_TYPE AC3ENC_TYPE_EAC3
-#include "ac3enc_opts_template.c"
-static AVClass eac3enc_class = { "E-AC-3 Encoder", av_default_item_name,
-                                 eac3_options, LIBAVUTIL_VERSION_INT };
-#else
-#define AC3ENC_TYPE AC3ENC_TYPE_AC3_FIXED
-#include "ac3enc_opts_template.c"
-static AVClass ac3enc_class = { "Fixed-Point AC-3 Encoder", av_default_item_name,
-                                ac3fixed_options, LIBAVUTIL_VERSION_INT };
-#endif
-
-
-/* prototypes for functions in ac3enc_fixed.c and ac3enc_float.c */
-
-static av_cold void mdct_end(AC3MDCTContext *mdct);
-
-static av_cold int mdct_init(AVCodecContext *avctx, AC3MDCTContext *mdct,
-                             int nbits);
-
-static void apply_window(DSPContext *dsp, SampleType *output, const SampleType *input,
-                         const SampleType *window, unsigned int len);
-
-static int normalize_samples(AC3EncodeContext *s);
-
-static void scale_coefficients(AC3EncodeContext *s);
-
-
 /**
  * LUT for number of exponent groups.
  * exponent_group_tab[coupling][exponent strategy-1][number of coefficients]
@@ -118,8 +77,7 @@ static uint8_t exponent_group_tab[2][3][256];
 /**
  * List of supported channel layouts.
  */
-#if CONFIG_AC3ENC_FLOAT || !CONFIG_AC3_FLOAT_ENCODER //we need this exactly once compiled in
-const int64_t ff_ac3_channel_layouts[] = {
+const int64_t ff_ac3_channel_layouts[19] = {
      AV_CH_LAYOUT_MONO,
      AV_CH_LAYOUT_STEREO,
      AV_CH_LAYOUT_2_1,
@@ -140,7 +98,6 @@ const int64_t ff_ac3_channel_layouts[] = {
      AV_CH_LAYOUT_5POINT1_BACK,
      0
 };
-#endif
 
 
 /**
@@ -233,60 +190,6 @@ static void adjust_frame_size(AC3EncodeContext *s)
 }
 
 
-/**
- * Deinterleave input samples.
- * Channels are reordered from FFmpeg's default order to AC-3 order.
- */
-static void deinterleave_input_samples(AC3EncodeContext *s,
-                                       const SampleType *samples)
-{
-    int ch, i;
-
-    /* deinterleave and remap input samples */
-    for (ch = 0; ch < s->channels; ch++) {
-        const SampleType *sptr;
-        int sinc;
-
-        /* copy last 256 samples of previous frame to the start of the current frame */
-        memcpy(&s->planar_samples[ch][0], &s->planar_samples[ch][AC3_FRAME_SIZE],
-               AC3_BLOCK_SIZE * sizeof(s->planar_samples[0][0]));
-
-        /* deinterleave */
-        sinc = s->channels;
-        sptr = samples + s->channel_map[ch];
-        for (i = AC3_BLOCK_SIZE; i < AC3_FRAME_SIZE+AC3_BLOCK_SIZE; i++) {
-            s->planar_samples[ch][i] = *sptr;
-            sptr += sinc;
-        }
-    }
-}
-
-
-/**
- * Apply the MDCT to input samples to generate frequency coefficients.
- * This applies the KBD window and normalizes the input to reduce precision
- * loss due to fixed-point calculations.
- */
-static void apply_mdct(AC3EncodeContext *s)
-{
-    int blk, ch;
-
-    for (ch = 0; ch < s->channels; ch++) {
-        for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
-            AC3Block *block = &s->blocks[blk];
-            const SampleType *input_samples = &s->planar_samples[ch][blk * AC3_BLOCK_SIZE];
-
-            apply_window(&s->dsp, s->windowed_samples, input_samples, s->mdct.window, AC3_WINDOW_SIZE);
-
-            block->coeff_shift[ch+1] = normalize_samples(s);
-
-            s->mdct.fft.mdct_calcw(&s->mdct.fft, block->mdct_coef[ch+1],
-                                   s->windowed_samples);
-        }
-    }
-}
-
-
 static void compute_coupling_strategy(AC3EncodeContext *s)
 {
     int blk, ch;
@@ -348,296 +251,6 @@ static void compute_coupling_strategy(AC3EncodeContext *s)
 }
 
 
-/**
- * Calculate a single coupling coordinate.
- */
-static inline float calc_cpl_coord(float energy_ch, float energy_cpl)
-{
-    float coord = 0.125;
-    if (energy_cpl > 0)
-        coord *= sqrtf(energy_ch / energy_cpl);
-    return coord;
-}
-
-
-/**
- * Calculate coupling channel and coupling coordinates.
- * TODO: Currently this is only used for the floating-point encoder. I was
- *       able to make it work for the fixed-point encoder, but quality was
- *       generally lower in most cases than not using coupling. If a more
- *       adaptive coupling strategy were to be implemented it might be useful
- *       at that time to use coupling for the fixed-point encoder as well.
- */
-static void apply_channel_coupling(AC3EncodeContext *s)
-{
-#if CONFIG_AC3ENC_FLOAT
-    LOCAL_ALIGNED_16(float,   cpl_coords,       [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
-    LOCAL_ALIGNED_16(int32_t, fixed_cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
-    int blk, ch, bnd, i, j;
-    CoefSumType energy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][16] = {{{0}}};
-    int num_cpl_coefs = s->num_cpl_subbands * 12;
-
-    memset(cpl_coords,       0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
-    memset(fixed_cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*fixed_cpl_coords));
-
-    /* calculate coupling channel from fbw channels */
-    for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
-        AC3Block *block = &s->blocks[blk];
-        CoefType *cpl_coef = &block->mdct_coef[CPL_CH][s->start_freq[CPL_CH]];
-        if (!block->cpl_in_use)
-            continue;
-        memset(cpl_coef-1, 0, (num_cpl_coefs+4) * sizeof(*cpl_coef));
-        for (ch = 1; ch <= s->fbw_channels; ch++) {
-            CoefType *ch_coef = &block->mdct_coef[ch][s->start_freq[CPL_CH]];
-            if (!block->channel_in_cpl[ch])
-                continue;
-            for (i = 0; i < num_cpl_coefs; i++)
-                cpl_coef[i] += ch_coef[i];
-        }
-        /* note: coupling start bin % 4 will always be 1 and num_cpl_coefs
-                 will always be a multiple of 12, so we need to subtract 1 from
-                 the start and add 4 to the length when using optimized
-                 functions which require 16-byte alignment. */
-
-        /* coefficients must be clipped to +/- 1.0 in order to be encoded */
-        s->dsp.vector_clipf(cpl_coef-1, cpl_coef-1, -1.0f, 1.0f, num_cpl_coefs+4);
-
-        /* scale coupling coefficients from float to 24-bit fixed-point */
-        s->ac3dsp.float_to_fixed24(&block->fixed_coef[CPL_CH][s->start_freq[CPL_CH]-1],
-                                   cpl_coef-1, num_cpl_coefs+4);
-    }
-
-    /* calculate energy in each band in coupling channel and each fbw channel */
-    /* TODO: possibly use SIMD to speed up energy calculation */
-    bnd = 0;
-    i = s->start_freq[CPL_CH];
-    while (i < s->cpl_end_freq) {
-        int band_size = s->cpl_band_sizes[bnd];
-        for (ch = CPL_CH; ch <= s->fbw_channels; ch++) {
-            for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
-                AC3Block *block = &s->blocks[blk];
-                if (!block->cpl_in_use || (ch > CPL_CH && !block->channel_in_cpl[ch]))
-                    continue;
-                for (j = 0; j < band_size; j++) {
-                    CoefType v = block->mdct_coef[ch][i+j];
-                    MAC_COEF(energy[blk][ch][bnd], v, v);
-                }
-            }
-        }
-        i += band_size;
-        bnd++;
-    }
-
-    /* determine which blocks to send new coupling coordinates for */
-    for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
-        AC3Block *block  = &s->blocks[blk];
-        AC3Block *block0 = blk ? &s->blocks[blk-1] : NULL;
-        int new_coords = 0;
-        CoefSumType coord_diff[AC3_MAX_CHANNELS] = {0,};
-
-        if (block->cpl_in_use) {
-            /* calculate coupling coordinates for all blocks and calculate the
-               average difference between coordinates in successive blocks */
-            for (ch = 1; ch <= s->fbw_channels; ch++) {
-                if (!block->channel_in_cpl[ch])
-                    continue;
-
-                for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
-                    cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy[blk][ch][bnd],
-                                                              energy[blk][CPL_CH][bnd]);
-                    if (blk > 0 && block0->cpl_in_use &&
-                        block0->channel_in_cpl[ch]) {
-                        coord_diff[ch] += fabs(cpl_coords[blk-1][ch][bnd] -
-                                               cpl_coords[blk  ][ch][bnd]);
-                    }
-                }
-                coord_diff[ch] /= s->num_cpl_bands;
-            }
-
-            /* send new coordinates if this is the first block, if previous
-             * block did not use coupling but this block does, the channels
-             * using coupling has changed from the previous block, or the
-             * coordinate difference from the last block for any channel is
-             * greater than a threshold value. */
-            if (blk == 0) {
-                new_coords = 1;
-            } else if (!block0->cpl_in_use) {
-                new_coords = 1;
-            } else {
-                for (ch = 1; ch <= s->fbw_channels; ch++) {
-                    if (block->channel_in_cpl[ch] && !block0->channel_in_cpl[ch]) {
-                        new_coords = 1;
-                        break;
-                    }
-                }
-                if (!new_coords) {
-                    for (ch = 1; ch <= s->fbw_channels; ch++) {
-                        if (block->channel_in_cpl[ch] && coord_diff[ch] > 0.04) {
-                            new_coords = 1;
-                            break;
-                        }
-                    }
-                }
-            }
-        }
-        block->new_cpl_coords = new_coords;
-    }
-
-    /* calculate final coupling coordinates, taking into account reusing of
-       coordinates in successive blocks */
-    for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
-        blk = 0;
-        while (blk < AC3_MAX_BLOCKS) {
-            int blk1;
-            CoefSumType energy_cpl;
-            AC3Block *block  = &s->blocks[blk];
-
-            if (!block->cpl_in_use) {
-                blk++;
-                continue;
-            }
-
-            energy_cpl = energy[blk][CPL_CH][bnd];
-            blk1 = blk+1;
-            while (!s->blocks[blk1].new_cpl_coords && blk1 < AC3_MAX_BLOCKS) {
-                if (s->blocks[blk1].cpl_in_use)
-                    energy_cpl += energy[blk1][CPL_CH][bnd];
-                blk1++;
-            }
-
-            for (ch = 1; ch <= s->fbw_channels; ch++) {
-                CoefType energy_ch;
-                if (!block->channel_in_cpl[ch])
-                    continue;
-                energy_ch = energy[blk][ch][bnd];
-                blk1 = blk+1;
-                while (!s->blocks[blk1].new_cpl_coords && blk1 < AC3_MAX_BLOCKS) {
-                    if (s->blocks[blk1].cpl_in_use)
-                        energy_ch += energy[blk1][ch][bnd];
-                    blk1++;
-                }
-                cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy_ch, energy_cpl);
-            }
-            blk = blk1;
-        }
-    }
-
-    /* calculate exponents/mantissas for coupling coordinates */
-    for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
-        AC3Block *block = &s->blocks[blk];
-        if (!block->cpl_in_use || !block->new_cpl_coords)
-            continue;
-
-        s->ac3dsp.float_to_fixed24(fixed_cpl_coords[blk][1],
-                                   cpl_coords[blk][1],
-                                   s->fbw_channels * 16);
-        s->ac3dsp.extract_exponents(block->cpl_coord_exp[1],
-                                    fixed_cpl_coords[blk][1],
-                                    s->fbw_channels * 16);
-
-        for (ch = 1; ch <= s->fbw_channels; ch++) {
-            int bnd, min_exp, max_exp, master_exp;
-
-            /* determine master exponent */
-            min_exp = max_exp = block->cpl_coord_exp[ch][0];
-            for (bnd = 1; bnd < s->num_cpl_bands; bnd++) {
-                int exp = block->cpl_coord_exp[ch][bnd];
-                min_exp = FFMIN(exp, min_exp);
-                max_exp = FFMAX(exp, max_exp);
-            }
-            master_exp = ((max_exp - 15) + 2) / 3;
-            master_exp = FFMAX(master_exp, 0);
-            while (min_exp < master_exp * 3)
-                master_exp--;
-            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
-                block->cpl_coord_exp[ch][bnd] = av_clip(block->cpl_coord_exp[ch][bnd] -
-                                                        master_exp * 3, 0, 15);
-            }
-            block->cpl_master_exp[ch] = master_exp;
-
-            /* quantize mantissas */
-            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
-                int cpl_exp  = block->cpl_coord_exp[ch][bnd];
-                int cpl_mant = (fixed_cpl_coords[blk][ch][bnd] << (5 + cpl_exp + master_exp * 3)) >> 24;
-                if (cpl_exp == 15)
-                    cpl_mant >>= 1;
-                else
-                    cpl_mant -= 16;
-
-                block->cpl_coord_mant[ch][bnd] = cpl_mant;
-            }
-        }
-    }
-
-    if (CONFIG_EAC3_ENCODER && s->eac3)
-        ff_eac3_set_cpl_states(s);
-#endif /* CONFIG_AC3ENC_FLOAT */
-}
-
-
-/**
- * Determine rematrixing flags for each block and band.
- */
-static void compute_rematrixing_strategy(AC3EncodeContext *s)
-{
-    int nb_coefs;
-    int blk, bnd, i;
-    AC3Block *block, *block0;
-
-    if (s->channel_mode != AC3_CHMODE_STEREO)
-        return;
-
-    for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
-        block = &s->blocks[blk];
-        block->new_rematrixing_strategy = !blk;
-
-        if (!s->rematrixing_enabled) {
-            block0 = block;
-            continue;
-        }
-
-        block->num_rematrixing_bands = 4;
-        if (block->cpl_in_use) {
-            block->num_rematrixing_bands -= (s->start_freq[CPL_CH] <= 61);
-            block->num_rematrixing_bands -= (s->start_freq[CPL_CH] == 37);
-            if (blk && block->num_rematrixing_bands != block0->num_rematrixing_bands)
-                block->new_rematrixing_strategy = 1;
-        }
-        nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
-
-        for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
-            /* calculate calculate sum of squared coeffs for one band in one block */
-            int start = ff_ac3_rematrix_band_tab[bnd];
-            int end   = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
-            CoefSumType sum[4] = {0,};
-            for (i = start; i < end; i++) {
-                CoefType lt = block->mdct_coef[1][i];
-                CoefType rt = block->mdct_coef[2][i];
-                CoefType md = lt + rt;
-                CoefType sd = lt - rt;
-                MAC_COEF(sum[0], lt, lt);
-                MAC_COEF(sum[1], rt, rt);
-                MAC_COEF(sum[2], md, md);
-                MAC_COEF(sum[3], sd, sd);
-            }
-
-            /* compare sums to determine if rematrixing will be used for this band */
-            if (FFMIN(sum[2], sum[3]) < FFMIN(sum[0], sum[1]))
-                block->rematrixing_flags[bnd] = 1;
-            else
-                block->rematrixing_flags[bnd] = 0;
-
-            /* determine if new rematrixing flags will be sent */
-            if (blk &&
-                block->rematrixing_flags[bnd] != block0->rematrixing_flags[bnd]) {
-                block->new_rematrixing_strategy = 1;
-            }
-        }
-        block0 = block;
-    }
-}
-
-
 /**
  * Apply stereo rematrixing to coefficients based on rematrixing flags.
  */
@@ -1470,7 +1083,7 @@ static int compute_bit_allocation(AC3EncodeContext *s)
         if (s->cpl_on) {
             s->cpl_on = 0;
             compute_coupling_strategy(s);
-            compute_rematrixing_strategy(s);
+            s->compute_rematrixing_strategy(s);
             apply_rematrixing(s);
             process_exponents(s);
             ret = compute_bit_allocation(s);
@@ -1510,20 +1123,14 @@ static inline int sym_quant(int c, int e, int levels)
  */
 static inline int asym_quant(int c, int e, int qbits)
 {
-    int lshift, m, v;
+    int m;
 
-    lshift = e + qbits - 24;
-    if (lshift >= 0)
-        v = c << lshift;
-    else
-        v = c >> (-lshift);
-    /* rounding */
-    v = (v + 1) >> 1;
+    c = (((c << e) >> (24 - qbits)) + 1) >> 1;
     m = (1 << (qbits-1));
-    if (v >= m)
-        v = m - 1;
-    av_assert2(v >= -m);
-    return v & ((1 << qbits)-1);
+    if (c >= m)
+        c = m - 1;
+    av_assert2(c >= -m);
+    return c;
 }
 
 
@@ -1532,7 +1139,7 @@ static inline int asym_quant(int c, int e, int qbits)
  */
 static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
                                       uint8_t *exp, uint8_t *bap,
-                                      uint16_t *qmant, int start_freq,
+                                      int16_t *qmant, int start_freq,
                                       int end_freq)
 {
     int i;
@@ -1884,14 +1491,14 @@ static void output_audio_block(AC3EncodeContext *s, int blk)
             q = block->qmant[ch][i];
             b = s->ref_bap[ch][blk][i];
             switch (b) {
-            case 0:                                         break;
-            case 1: if (q != 128) put_bits(&s->pb,   5, q); break;
-            case 2: if (q != 128) put_bits(&s->pb,   7, q); break;
-            case 3:               put_bits(&s->pb,   3, q); break;
-            case 4: if (q != 128) put_bits(&s->pb,   7, q); break;
-            case 14:              put_bits(&s->pb,  14, q); break;
-            case 15:              put_bits(&s->pb,  16, q); break;
-            default:              put_bits(&s->pb, b-1, q); break;
+            case 0:                                          break;
+            case 1: if (q != 128) put_bits (&s->pb,   5, q); break;
+            case 2: if (q != 128) put_bits (&s->pb,   7, q); break;
+            case 3:               put_sbits(&s->pb,   3, q); break;
+            case 4: if (q != 128) put_bits (&s->pb,   7, q); break;
+            case 14:              put_sbits(&s->pb,  14, q); break;
+            case 15:              put_sbits(&s->pb,  16, q); break;
+            default:              put_sbits(&s->pb, b-1, q); break;
             }
         }
         if (ch == CPL_CH)
@@ -1990,10 +1597,7 @@ static void output_frame(AC3EncodeContext *s, unsigned char *frame)
 
     init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);
 
-    if (CONFIG_EAC3_ENCODER && s->eac3)
-        ff_eac3_output_frame_header(s);
-    else
-        ac3_output_frame_header(s);
+    s->output_frame_header(s);
 
     for (blk = 0; blk < AC3_MAX_BLOCKS; blk++)
         output_audio_block(s, blk);
@@ -2268,8 +1872,8 @@ static int validate_metadata(AVCodecContext *avctx)
 /**
  * Encode a single AC-3 frame.
  */
-static int ac3_encode_frame(AVCodecContext *avctx, unsigned char *frame,
-                            int buf_size, void *data)
+int ff_ac3_encode_frame(AVCodecContext *avctx, unsigned char *frame,
+                        int buf_size, void *data)
 {
     AC3EncodeContext *s = avctx->priv_data;
     const SampleType *samples = data;
@@ -2284,19 +1888,19 @@ static int ac3_encode_frame(AVCodecContext *avctx, unsigned char *frame,
     if (s->bit_alloc.sr_code == 1 || s->eac3)
         adjust_frame_size(s);
 
-    deinterleave_input_samples(s, samples);
+    s->deinterleave_input_samples(s, samples);
 
-    apply_mdct(s);
+    s->apply_mdct(s);
 
-    scale_coefficients(s);
+    s->scale_coefficients(s);
 
     s->cpl_on = s->cpl_enabled;
     compute_coupling_strategy(s);
 
     if (s->cpl_on)
-        apply_channel_coupling(s);
+        s->apply_channel_coupling(s);
 
-    compute_rematrixing_strategy(s);
+    s->compute_rematrixing_strategy(s);
 
     apply_rematrixing(s);
 
@@ -2319,11 +1923,12 @@ static int ac3_encode_frame(AVCodecContext *avctx, unsigned char *frame,
 /**
  * Finalize encoding and free any memory allocated by the encoder.
  */
-static av_cold int ac3_encode_close(AVCodecContext *avctx)
+av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
 {
     int blk, ch;
     AC3EncodeContext *s = avctx->priv_data;
 
+    av_freep(&s->windowed_samples);
     for (ch = 0; ch < s->channels; ch++)
         av_freep(&s->planar_samples[ch]);
     av_freep(&s->planar_samples);
@@ -2349,7 +1954,8 @@ static av_cold int ac3_encode_close(AVCodecContext *avctx)
         av_freep(&block->qmant);
     }
 
-    mdct_end(&s->mdct);
+    s->mdct_end(s->mdct);
+    av_freep(&s->mdct);
 
     av_freep(&avctx->coded_frame);
     return 0;
@@ -2519,8 +2125,7 @@ static av_cold int validate_options(AVCodecContext *avctx, AC3EncodeContext *s)
                              (s->channel_mode == AC3_CHMODE_STEREO);
 
     s->cpl_enabled = s->options.channel_coupling &&
-                     s->channel_mode >= AC3_CHMODE_STEREO &&
-                     CONFIG_AC3ENC_FLOAT;
+                     s->channel_mode >= AC3_CHMODE_STEREO && !s->fixed_point;
 
     return 0;
 }
@@ -2604,13 +2209,9 @@ static av_cold int allocate_buffers(AVCodecContext *avctx)
     AC3EncodeContext *s = avctx->priv_data;
     int channels = s->channels + 1; /* includes coupling channel */
 
-    FF_ALLOC_OR_GOTO(avctx, s->planar_samples, s->channels * sizeof(*s->planar_samples),
-                     alloc_fail);
-    for (ch = 0; ch < s->channels; ch++) {
-        FF_ALLOCZ_OR_GOTO(avctx, s->planar_samples[ch],
-                          (AC3_FRAME_SIZE+AC3_BLOCK_SIZE) * sizeof(**s->planar_samples),
-                          alloc_fail);
-    }
+    if (s->allocate_sample_buffers(s))
+        goto alloc_fail;
+
     FF_ALLOC_OR_GOTO(avctx, s->bap_buffer,  AC3_MAX_BLOCKS * channels *
                      AC3_MAX_COEFS * sizeof(*s->bap_buffer),  alloc_fail);
     FF_ALLOC_OR_GOTO(avctx, s->bap1_buffer, AC3_MAX_BLOCKS * channels *
@@ -2676,7 +2277,7 @@ static av_cold int allocate_buffers(AVCodecContext *avctx)
         }
     }
 
-    if (CONFIG_AC3ENC_FLOAT) {
+    if (!s->fixed_point) {
         FF_ALLOCZ_OR_GOTO(avctx, s->fixed_coef_buffer, AC3_MAX_BLOCKS * channels *
                           AC3_MAX_COEFS * sizeof(*s->fixed_coef_buffer), alloc_fail);
         for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
@@ -2705,11 +2306,13 @@ alloc_fail:
 /**
  * Initialize the encoder.
  */
-static av_cold int ac3_encode_init(AVCodecContext *avctx)
+av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
 {
     AC3EncodeContext *s = avctx->priv_data;
     int ret, frame_size_58;
 
+    s->avctx = avctx;
+
     s->eac3 = avctx->codec_id == CODEC_ID_EAC3;
 
     avctx->frame_size = AC3_FRAME_SIZE;
@@ -2735,13 +2338,42 @@ static av_cold int ac3_encode_init(AVCodecContext *avctx)
         s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
     }
 
+    /* set function pointers */
+    if (CONFIG_AC3_FIXED_ENCODER && s->fixed_point) {
+        s->mdct_end                     = ff_ac3_fixed_mdct_end;
+        s->mdct_init                    = ff_ac3_fixed_mdct_init;
+        s->apply_window                 = ff_ac3_fixed_apply_window;
+        s->normalize_samples            = ff_ac3_fixed_normalize_samples;
+        s->scale_coefficients           = ff_ac3_fixed_scale_coefficients;
+        s->allocate_sample_buffers      = ff_ac3_fixed_allocate_sample_buffers;
+        s->deinterleave_input_samples   = ff_ac3_fixed_deinterleave_input_samples;
+        s->apply_mdct                   = ff_ac3_fixed_apply_mdct;
+        s->apply_channel_coupling       = ff_ac3_fixed_apply_channel_coupling;
+        s->compute_rematrixing_strategy = ff_ac3_fixed_compute_rematrixing_strategy;
+    } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) {
+        s->mdct_end                     = ff_ac3_float_mdct_end;
+        s->mdct_init                    = ff_ac3_float_mdct_init;
+        s->apply_window                 = ff_ac3_float_apply_window;
+        s->scale_coefficients           = ff_ac3_float_scale_coefficients;
+        s->allocate_sample_buffers      = ff_ac3_float_allocate_sample_buffers;
+        s->deinterleave_input_samples   = ff_ac3_float_deinterleave_input_samples;
+        s->apply_mdct                   = ff_ac3_float_apply_mdct;
+        s->apply_channel_coupling       = ff_ac3_float_apply_channel_coupling;
+        s->compute_rematrixing_strategy = ff_ac3_float_compute_rematrixing_strategy;
+    }
+    if (CONFIG_EAC3_ENCODER && s->eac3)
+        s->output_frame_header = ff_eac3_output_frame_header;
+    else
+        s->output_frame_header = ac3_output_frame_header;
+
     set_bandwidth(s);
 
     exponent_init(s);
 
     bit_alloc_init(s);
 
-    ret = mdct_init(avctx, &s->mdct, 9);
+    FF_ALLOCZ_OR_GOTO(avctx, s->mdct, sizeof(AC3MDCTContext), init_fail);
+    ret = s->mdct_init(avctx, s->mdct, 9);
     if (ret)
         goto init_fail;
 
@@ -2758,6 +2390,6 @@ static av_cold int ac3_encode_init(AVCodecContext *avctx)
 
     return 0;
 init_fail:
-    ac3_encode_close(avctx);
+    ff_ac3_encode_close(avctx);
     return ret;
 }