PeerStreamer

/*

 * VC3/DNxHD encoder

 * Copyright (c) 2007 Baptiste Coudurier <baptiste dot coudurier at smartjog dot com>

 *

 * VC-3 encoder funded by the British Broadcasting Corporation

 *

 * 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

 */

//#define DEBUG

#define RC_VARIANCE 1 // use variance or ssd for fast rc

#include "avcodec.h"

#include "dsputil.h"

#include "mpegvideo.h"

#include "dnxhdenc.h"

int dct_quantize_c(MpegEncContext *s, DCTELEM *block, int n, int qscale, int *overflow);

#define LAMBDA_FRAC_BITS 10

static av_always_inline void dnxhd_get_pixels_8x4(DCTELEM *restrict block, const uint8_t *pixels, int line_size)

{

    int i;

    for (i = 0; i < 4; i++) {

        block[0] = pixels[0]; block[1] = pixels[1];

        block[2] = pixels[2]; block[3] = pixels[3];

        block[4] = pixels[4]; block[5] = pixels[5];

        block[6] = pixels[6]; block[7] = pixels[7];

        pixels += line_size;

        block += 8;

    }

    memcpy(block   , block- 8, sizeof(*block)*8);

    memcpy(block+ 8, block-16, sizeof(*block)*8);

    memcpy(block+16, block-24, sizeof(*block)*8);

    memcpy(block+24, block-32, sizeof(*block)*8);

}

static int dnxhd_init_vlc(DNXHDEncContext *ctx)

{

    int i, j, level, run;

    int max_level = 1<<(ctx->cid_table->bit_depth+2);

    CHECKED_ALLOCZ(ctx->vlc_codes, max_level*4*sizeof(*ctx->vlc_codes));

    CHECKED_ALLOCZ(ctx->vlc_bits,  max_level*4*sizeof(*ctx->vlc_bits));

    CHECKED_ALLOCZ(ctx->run_codes, 63*2);

    CHECKED_ALLOCZ(ctx->run_bits,    63);

    ctx->vlc_codes += max_level*2;

    ctx->vlc_bits  += max_level*2;

    for (level = -max_level; level < max_level; level++) {

        for (run = 0; run < 2; run++) {

            int index = (level<<1)|run;

            int sign, offset = 0, alevel = level;

            MASK_ABS(sign, alevel);

            if (alevel > 64) {

                offset = (alevel-1)>>6;

                alevel -= offset<<6;

            }

            for (j = 0; j < 257; j++) {

                if (ctx->cid_table->ac_level[j] == alevel &&

                    (!offset || (ctx->cid_table->ac_index_flag[j] && offset)) &&

                    (!run    || (ctx->cid_table->ac_run_flag  [j] && run))) {

                    assert(!ctx->vlc_codes[index]);

                    if (alevel) {

                        ctx->vlc_codes[index] = (ctx->cid_table->ac_codes[j]<<1)|(sign&1);

                        ctx->vlc_bits [index] = ctx->cid_table->ac_bits[j]+1;

                    } else {

                        ctx->vlc_codes[index] = ctx->cid_table->ac_codes[j];

                        ctx->vlc_bits [index] = ctx->cid_table->ac_bits [j];

                    }

                    break;

                }

            }

            assert(!alevel || j < 257);

            if (offset) {

                ctx->vlc_codes[index] = (ctx->vlc_codes[index]<<ctx->cid_table->index_bits)|offset;

                ctx->vlc_bits [index]+= ctx->cid_table->index_bits;

            }

        }

    }

    for (i = 0; i < 62; i++) {

        int run = ctx->cid_table->run[i];

        assert(run < 63);

        ctx->run_codes[run] = ctx->cid_table->run_codes[i];

        ctx->run_bits [run] = ctx->cid_table->run_bits[i];

    }

    return 0;

 fail:

    return -1;

}

static int dnxhd_init_qmat(DNXHDEncContext *ctx, int lbias, int cbias)

{

    // init first elem to 1 to avoid div by 0 in convert_matrix

    uint16_t weight_matrix[64] = {1,}; // convert_matrix needs uint16_t*

    int qscale, i;

    CHECKED_ALLOCZ(ctx->qmatrix_l,   (ctx->m.avctx->qmax+1) * 64 * sizeof(int));

    CHECKED_ALLOCZ(ctx->qmatrix_c,   (ctx->m.avctx->qmax+1) * 64 * sizeof(int));

    CHECKED_ALLOCZ(ctx->qmatrix_l16, (ctx->m.avctx->qmax+1) * 64 * 2 * sizeof(uint16_t));

    CHECKED_ALLOCZ(ctx->qmatrix_c16, (ctx->m.avctx->qmax+1) * 64 * 2 * sizeof(uint16_t));

    for (i = 1; i < 64; i++) {

        int j = ctx->m.dsp.idct_permutation[ff_zigzag_direct[i]];

        weight_matrix[j] = ctx->cid_table->luma_weight[i];

    }

    ff_convert_matrix(&ctx->m.dsp, ctx->qmatrix_l, ctx->qmatrix_l16, weight_matrix,

                      ctx->m.intra_quant_bias, 1, ctx->m.avctx->qmax, 1);

    for (i = 1; i < 64; i++) {

        int j = ctx->m.dsp.idct_permutation[ff_zigzag_direct[i]];

        weight_matrix[j] = ctx->cid_table->chroma_weight[i];

    }

    ff_convert_matrix(&ctx->m.dsp, ctx->qmatrix_c, ctx->qmatrix_c16, weight_matrix,

                      ctx->m.intra_quant_bias, 1, ctx->m.avctx->qmax, 1);

    for (qscale = 1; qscale <= ctx->m.avctx->qmax; qscale++) {

        for (i = 0; i < 64; i++) {

            ctx->qmatrix_l  [qscale]   [i] <<= 2; ctx->qmatrix_c  [qscale]   [i] <<= 2;

            ctx->qmatrix_l16[qscale][0][i] <<= 2; ctx->qmatrix_l16[qscale][1][i] <<= 2;

            ctx->qmatrix_c16[qscale][0][i] <<= 2; ctx->qmatrix_c16[qscale][1][i] <<= 2;

        }

    }

    return 0;

 fail:

    return -1;

}

static int dnxhd_init_rc(DNXHDEncContext *ctx)

{

    CHECKED_ALLOCZ(ctx->mb_rc, 8160*ctx->m.avctx->qmax*sizeof(RCEntry));

    if (ctx->m.avctx->mb_decision != FF_MB_DECISION_RD)

        CHECKED_ALLOCZ(ctx->mb_cmp, ctx->m.mb_num*sizeof(RCCMPEntry));

    ctx->frame_bits = (ctx->cid_table->coding_unit_size - 640 - 4) * 8;

    ctx->qscale = 1;

    ctx->lambda = 2<<LAMBDA_FRAC_BITS; // qscale 2

    return 0;

 fail:

    return -1;

}

static int dnxhd_encode_init(AVCodecContext *avctx)

{

    DNXHDEncContext *ctx = avctx->priv_data;

    int i, index;

    ctx->cid = ff_dnxhd_find_cid(avctx);

    if (!ctx->cid || avctx->pix_fmt != PIX_FMT_YUV422P) {

        av_log(avctx, AV_LOG_ERROR, "video parameters incompatible with DNxHD\n");

        return -1;

    }

    av_log(avctx, AV_LOG_DEBUG, "cid %d\n", ctx->cid);

    index = ff_dnxhd_get_cid_table(ctx->cid);

    ctx->cid_table = &ff_dnxhd_cid_table[index];

    ctx->m.avctx = avctx;

    ctx->m.mb_intra = 1;

    ctx->m.h263_aic = 1;

    dsputil_init(&ctx->m.dsp, avctx);

    ff_dct_common_init(&ctx->m);

    if (!ctx->m.dct_quantize)

        ctx->m.dct_quantize = dct_quantize_c;

    ctx->m.mb_height = (avctx->height + 15) / 16;

    ctx->m.mb_width  = (avctx->width  + 15) / 16;

    if (avctx->flags & CODEC_FLAG_INTERLACED_DCT) {

        ctx->interlaced = 1;

        ctx->m.mb_height /= 2;

    }

    ctx->m.mb_num = ctx->m.mb_height * ctx->m.mb_width;

    if (avctx->intra_quant_bias != FF_DEFAULT_QUANT_BIAS)

        ctx->m.intra_quant_bias = avctx->intra_quant_bias;

    if (dnxhd_init_qmat(ctx, ctx->m.intra_quant_bias, 0) < 0) // XXX tune lbias/cbias

        return -1;

    if (dnxhd_init_vlc(ctx) < 0)

        return -1;

    if (dnxhd_init_rc(ctx) < 0)

        return -1;

    CHECKED_ALLOCZ(ctx->slice_size, ctx->m.mb_height*sizeof(uint32_t));

    CHECKED_ALLOCZ(ctx->mb_bits,    ctx->m.mb_num   *sizeof(uint16_t));

    CHECKED_ALLOCZ(ctx->mb_qscale,  ctx->m.mb_num   *sizeof(uint8_t));

    ctx->frame.key_frame = 1;

    ctx->frame.pict_type = FF_I_TYPE;

    ctx->m.avctx->coded_frame = &ctx->frame;

    if (avctx->thread_count > MAX_THREADS || (avctx->thread_count > ctx->m.mb_height)) {

        av_log(avctx, AV_LOG_ERROR, "too many threads\n");

        return -1;

    }

    ctx->thread[0] = ctx;

    for (i = 1; i < avctx->thread_count; i++) {

        ctx->thread[i] =  av_malloc(sizeof(DNXHDEncContext));

        memcpy(ctx->thread[i], ctx, sizeof(DNXHDEncContext));

    }

    for (i = 0; i < avctx->thread_count; i++) {

        ctx->thread[i]->m.start_mb_y = (ctx->m.mb_height*(i  ) + avctx->thread_count/2) / avctx->thread_count;

        ctx->thread[i]->m.end_mb_y   = (ctx->m.mb_height*(i+1) + avctx->thread_count/2) / avctx->thread_count;

    }

    return 0;

 fail: //for CHECKED_ALLOCZ

    return -1;

}

static int dnxhd_write_header(AVCodecContext *avctx, uint8_t *buf)

{

    DNXHDEncContext *ctx = avctx->priv_data;

    const uint8_t header_prefix[5] = { 0x00,0x00,0x02,0x80,0x01 };

    memcpy(buf, header_prefix, 5);

    buf[5] = ctx->interlaced ? ctx->cur_field+2 : 0x01;

    buf[6] = 0x80; // crc flag off

    buf[7] = 0xa0; // reserved

    AV_WB16(buf + 0x18, avctx->height); // ALPF

    AV_WB16(buf + 0x1a, avctx->width);  // SPL

    AV_WB16(buf + 0x1d, avctx->height); // NAL

    buf[0x21] = 0x38; // FIXME 8 bit per comp

    buf[0x22] = 0x88 + (ctx->frame.interlaced_frame<<2);

    AV_WB32(buf + 0x28, ctx->cid); // CID

    buf[0x2c] = ctx->interlaced ? 0 : 0x80;

    buf[0x5f] = 0x01; // UDL

    buf[0x167] = 0x02; // reserved

    AV_WB16(buf + 0x16a, ctx->m.mb_height * 4 + 4); // MSIPS

    buf[0x16d] = ctx->m.mb_height; // Ns

    buf[0x16f] = 0x10; // reserved

    ctx->msip = buf + 0x170;

    return 0;

}

static av_always_inline void dnxhd_encode_dc(DNXHDEncContext *ctx, int diff)

{

    int nbits;

    if (diff < 0) {

        nbits = av_log2_16bit(-2*diff);

        diff--;

    } else {

        nbits = av_log2_16bit(2*diff);

    }

    put_bits(&ctx->m.pb, ctx->cid_table->dc_bits[nbits] + nbits,

             (ctx->cid_table->dc_codes[nbits]<<nbits) + (diff & ((1 << nbits) - 1)));

}

static av_always_inline void dnxhd_encode_block(DNXHDEncContext *ctx, DCTELEM *block, int last_index, int n)

{

    int last_non_zero = 0;

    int slevel, i, j;

    dnxhd_encode_dc(ctx, block[0] - ctx->m.last_dc[n]);

    ctx->m.last_dc[n] = block[0];

    for (i = 1; i <= last_index; i++) {

        j = ctx->m.intra_scantable.permutated[i];

        slevel = block[j];

        if (slevel) {

            int run_level = i - last_non_zero - 1;

            int rlevel = (slevel<<1)|!!run_level;

            put_bits(&ctx->m.pb, ctx->vlc_bits[rlevel], ctx->vlc_codes[rlevel]);

            if (run_level)

                put_bits(&ctx->m.pb, ctx->run_bits[run_level], ctx->run_codes[run_level]);

            last_non_zero = i;

        }

    }

    put_bits(&ctx->m.pb, ctx->vlc_bits[0], ctx->vlc_codes[0]); // EOB

}

static av_always_inline void dnxhd_unquantize_c(DNXHDEncContext *ctx, DCTELEM *block, int n, int qscale, int last_index)

{

    const uint8_t *weight_matrix;

    int level;

    int i;

    weight_matrix = (n&2) ? ctx->cid_table->chroma_weight : ctx->cid_table->luma_weight;

    for (i = 1; i <= last_index; i++) {

        int j = ctx->m.intra_scantable.permutated[i];

        level = block[j];

        if (level) {

            if (level < 0) {

                level = (1-2*level) * qscale * weight_matrix[i];

                if (weight_matrix[i] != 32)

                    level += 32;

                level >>= 6;

                level = -level;

            } else {

                level = (2*level+1) * qscale * weight_matrix[i];

                if (weight_matrix[i] != 32)

                    level += 32;

                level >>= 6;

            }

            block[j] = level;

        }

    }

}

static av_always_inline int dnxhd_ssd_block(DCTELEM *qblock, DCTELEM *block)

{

    int score = 0;

    int i;

    for (i = 0; i < 64; i++)

        score += (block[i]-qblock[i])*(block[i]-qblock[i]);

    return score;

}

static av_always_inline int dnxhd_calc_ac_bits(DNXHDEncContext *ctx, DCTELEM *block, int last_index)

{

    int last_non_zero = 0;

    int bits = 0;

    int i, j, level;

    for (i = 1; i <= last_index; i++) {

        j = ctx->m.intra_scantable.permutated[i];

        level = block[j];

        if (level) {

            int run_level = i - last_non_zero - 1;

            bits += ctx->vlc_bits[(level<<1)|!!run_level]+ctx->run_bits[run_level];

            last_non_zero = i;

        }

    }

    return bits;

}

static av_always_inline void dnxhd_get_blocks(DNXHDEncContext *ctx, int mb_x, int mb_y)

{

    const uint8_t *ptr_y = ctx->thread[0]->src[0] + ((mb_y << 4) * ctx->m.linesize)   + (mb_x << 4);

    const uint8_t *ptr_u = ctx->thread[0]->src[1] + ((mb_y << 4) * ctx->m.uvlinesize) + (mb_x << 3);

    const uint8_t *ptr_v = ctx->thread[0]->src[2] + ((mb_y << 4) * ctx->m.uvlinesize) + (mb_x << 3);

    DSPContext *dsp = &ctx->m.dsp;

    dsp->get_pixels(ctx->blocks[0], ptr_y    , ctx->m.linesize);

    dsp->get_pixels(ctx->blocks[1], ptr_y + 8, ctx->m.linesize);

    dsp->get_pixels(ctx->blocks[2], ptr_u    , ctx->m.uvlinesize);

    dsp->get_pixels(ctx->blocks[3], ptr_v    , ctx->m.uvlinesize);

    if (mb_y+1 == ctx->m.mb_height && ctx->m.avctx->height == 1080) {

        if (ctx->interlaced) {

            dnxhd_get_pixels_8x4(ctx->blocks[4], ptr_y + ctx->dct_y_offset    , ctx->m.linesize);

            dnxhd_get_pixels_8x4(ctx->blocks[5], ptr_y + ctx->dct_y_offset + 8, ctx->m.linesize);

            dnxhd_get_pixels_8x4(ctx->blocks[6], ptr_u + ctx->dct_uv_offset   , ctx->m.uvlinesize);

            dnxhd_get_pixels_8x4(ctx->blocks[7], ptr_v + ctx->dct_uv_offset   , ctx->m.uvlinesize);

        } else {

            dsp->clear_block(ctx->blocks[4]); dsp->clear_block(ctx->blocks[5]);

            dsp->clear_block(ctx->blocks[6]); dsp->clear_block(ctx->blocks[7]);

        }

    } else {

        dsp->get_pixels(ctx->blocks[4], ptr_y + ctx->dct_y_offset    , ctx->m.linesize);

        dsp->get_pixels(ctx->blocks[5], ptr_y + ctx->dct_y_offset + 8, ctx->m.linesize);

        dsp->get_pixels(ctx->blocks[6], ptr_u + ctx->dct_uv_offset   , ctx->m.uvlinesize);

        dsp->get_pixels(ctx->blocks[7], ptr_v + ctx->dct_uv_offset   , ctx->m.uvlinesize);

    }

}

static av_always_inline int dnxhd_switch_matrix(DNXHDEncContext *ctx, int i)

{

    if (i&2) {

        ctx->m.q_intra_matrix16 = ctx->qmatrix_c16;

        ctx->m.q_intra_matrix   = ctx->qmatrix_c;

        return 1 + (i&1);

    } else {

        ctx->m.q_intra_matrix16 = ctx->qmatrix_l16;

        ctx->m.q_intra_matrix   = ctx->qmatrix_l;

        return 0;

    }

}

static int dnxhd_calc_bits_thread(AVCodecContext *avctx, void *arg)

{

    DNXHDEncContext *ctx = *(void**)arg;

    int mb_y, mb_x;

    int qscale = ctx->thread[0]->qscale;

    for (mb_y = ctx->m.start_mb_y; mb_y < ctx->m.end_mb_y; mb_y++) {

        ctx->m.last_dc[0] =

        ctx->m.last_dc[1] =

        ctx->m.last_dc[2] = 1024;

        for (mb_x = 0; mb_x < ctx->m.mb_width; mb_x++) {

            unsigned mb = mb_y * ctx->m.mb_width + mb_x;

            int ssd     = 0;

            int ac_bits = 0;

            int dc_bits = 0;

            int i;

            dnxhd_get_blocks(ctx, mb_x, mb_y);

            for (i = 0; i < 8; i++) {

                DECLARE_ALIGNED_16(DCTELEM, block[64]);

                DCTELEM *src_block = ctx->blocks[i];

                int overflow, nbits, diff, last_index;

                int n = dnxhd_switch_matrix(ctx, i);

                memcpy(block, src_block, sizeof(block));

                last_index = ctx->m.dct_quantize((MpegEncContext*)ctx, block, i, qscale, &overflow);

                ac_bits += dnxhd_calc_ac_bits(ctx, block, last_index);

                diff = block[0] - ctx->m.last_dc[n];

                if (diff < 0) nbits = av_log2_16bit(-2*diff);

                else          nbits = av_log2_16bit( 2*diff);

                dc_bits += ctx->cid_table->dc_bits[nbits] + nbits;

                ctx->m.last_dc[n] = block[0];

                if (avctx->mb_decision == FF_MB_DECISION_RD || !RC_VARIANCE) {

                    dnxhd_unquantize_c(ctx, block, i, qscale, last_index);

                    ctx->m.dsp.idct(block);

                    ssd += dnxhd_ssd_block(block, src_block);

                }

            }

            ctx->mb_rc[qscale][mb].ssd = ssd;

            ctx->mb_rc[qscale][mb].bits = ac_bits+dc_bits+12+8*ctx->vlc_bits[0];

        }

    }

    return 0;

}

static int dnxhd_encode_thread(AVCodecContext *avctx, void *arg)

{

    DNXHDEncContext *ctx = *(void**)arg;

    int mb_y, mb_x;

    for (mb_y = ctx->m.start_mb_y; mb_y < ctx->m.end_mb_y; mb_y++) {

        ctx->m.last_dc[0] =

        ctx->m.last_dc[1] =

        ctx->m.last_dc[2] = 1024;

        for (mb_x = 0; mb_x < ctx->m.mb_width; mb_x++) {

            unsigned mb = mb_y * ctx->m.mb_width + mb_x;

            int qscale = ctx->mb_qscale[mb];

            int i;

            put_bits(&ctx->m.pb, 12, qscale<<1);

            dnxhd_get_blocks(ctx, mb_x, mb_y);

            for (i = 0; i < 8; i++) {

                DCTELEM *block = ctx->blocks[i];

                int last_index, overflow;

                int n = dnxhd_switch_matrix(ctx, i);

                last_index = ctx->m.dct_quantize((MpegEncContext*)ctx, block, i, qscale, &overflow);

                //START_TIMER;

                dnxhd_encode_block(ctx, block, last_index, n);

                //STOP_TIMER("encode_block");

            }

        }

        if (put_bits_count(&ctx->m.pb)&31)

            put_bits(&ctx->m.pb, 32-(put_bits_count(&ctx->m.pb)&31), 0);

    }

    flush_put_bits(&ctx->m.pb);

    return 0;

}

static void dnxhd_setup_threads_slices(DNXHDEncContext *ctx, uint8_t *buf)

{

    int mb_y, mb_x;

    int i, offset = 0;

    for (i = 0; i < ctx->m.avctx->thread_count; i++) {

        int thread_size = 0;

        for (mb_y = ctx->thread[i]->m.start_mb_y; mb_y < ctx->thread[i]->m.end_mb_y; mb_y++) {

            ctx->slice_size[mb_y] = 0;

            for (mb_x = 0; mb_x < ctx->m.mb_width; mb_x++) {

                unsigned mb = mb_y * ctx->m.mb_width + mb_x;

                ctx->slice_size[mb_y] += ctx->mb_bits[mb];

            }

            ctx->slice_size[mb_y] = (ctx->slice_size[mb_y]+31)&~31;

            ctx->slice_size[mb_y] >>= 3;

            thread_size += ctx->slice_size[mb_y];

        }

        init_put_bits(&ctx->thread[i]->m.pb, buf + 640 + offset, thread_size);

        offset += thread_size;

    }

}

static int dnxhd_mb_var_thread(AVCodecContext *avctx, void *arg)

{

    DNXHDEncContext *ctx = *(void**)arg;

    int mb_y, mb_x;

    for (mb_y = ctx->m.start_mb_y; mb_y < ctx->m.end_mb_y; mb_y++) {

        for (mb_x = 0; mb_x < ctx->m.mb_width; mb_x++) {

            unsigned mb  = mb_y * ctx->m.mb_width + mb_x;

            uint8_t *pix = ctx->thread[0]->src[0] + ((mb_y<<4) * ctx->m.linesize) + (mb_x<<4);

            int sum      = ctx->m.dsp.pix_sum(pix, ctx->m.linesize);

            int varc     = (ctx->m.dsp.pix_norm1(pix, ctx->m.linesize) - (((unsigned)(sum*sum))>>8)+128)>>8;

            ctx->mb_cmp[mb].value = varc;

            ctx->mb_cmp[mb].mb = mb;

        }

    }

    return 0;

}

static int dnxhd_encode_rdo(AVCodecContext *avctx, DNXHDEncContext *ctx)

{

    int lambda, up_step, down_step;

    int last_lower = INT_MAX, last_higher = 0;

    int x, y, q;

    for (q = 1; q < avctx->qmax; q++) {

        ctx->qscale = q;

        avctx->execute(avctx, dnxhd_calc_bits_thread, (void**)&ctx->thread[0], NULL, avctx->thread_count, sizeof(void*));

    }

    up_step = down_step = 2<<LAMBDA_FRAC_BITS;

    lambda = ctx->lambda;

    for (;;) {

        int bits = 0;

        int end = 0;

        if (lambda == last_higher) {

            lambda++;

            end = 1; // need to set final qscales/bits

        }

        for (y = 0; y < ctx->m.mb_height; y++) {

            for (x = 0; x < ctx->m.mb_width; x++) {

                unsigned min = UINT_MAX;

                int qscale = 1;

                int mb = y*ctx->m.mb_width+x;

                for (q = 1; q < avctx->qmax; q++) {

                    unsigned score = ctx->mb_rc[q][mb].bits*lambda+(ctx->mb_rc[q][mb].ssd<<LAMBDA_FRAC_BITS);

                    if (score < min) {

                        min = score;

                        qscale = q;

                    }

                }

                bits += ctx->mb_rc[qscale][mb].bits;

                ctx->mb_qscale[mb] = qscale;

                ctx->mb_bits[mb] = ctx->mb_rc[qscale][mb].bits;

            }

            bits = (bits+31)&~31; // padding

            if (bits > ctx->frame_bits)

                break;

        }

        //dprintf(ctx->m.avctx, "lambda %d, up %u, down %u, bits %d, frame %d\n",

        //        lambda, last_higher, last_lower, bits, ctx->frame_bits);

        if (end) {

            if (bits > ctx->frame_bits)

                return -1;

            break;

        }

        if (bits < ctx->frame_bits) {

            last_lower = FFMIN(lambda, last_lower);

            if (last_higher != 0)

                lambda = (lambda+last_higher)>>1;

            else

                lambda -= down_step;

            down_step *= 5; // XXX tune ?

            up_step = 1<<LAMBDA_FRAC_BITS;

            lambda = FFMAX(1, lambda);

            if (lambda == last_lower)

                break;

        } else {

            last_higher = FFMAX(lambda, last_higher);

            if (last_lower != INT_MAX)

                lambda = (lambda+last_lower)>>1;

            else

                lambda += up_step;

            up_step *= 5;

            down_step = 1<<LAMBDA_FRAC_BITS;

        }

    }

    //dprintf(ctx->m.avctx, "out lambda %d\n", lambda);

    ctx->lambda = lambda;

    return 0;

}

static int dnxhd_find_qscale(DNXHDEncContext *ctx)

{

    int bits = 0;

    int up_step = 1;

    int down_step = 1;

    int last_higher = 0;

    int last_lower = INT_MAX;

    int qscale;

    int x, y;

    qscale = ctx->qscale;

    for (;;) {

        bits = 0;

        ctx->qscale = qscale;

        // XXX avoid recalculating bits

        ctx->m.avctx->execute(ctx->m.avctx, dnxhd_calc_bits_thread, (void**)&ctx->thread[0], NULL, ctx->m.avctx->thread_count, sizeof(void*));

        for (y = 0; y < ctx->m.mb_height; y++) {

            for (x = 0; x < ctx->m.mb_width; x++)

                bits += ctx->mb_rc[qscale][y*ctx->m.mb_width+x].bits;

            bits = (bits+31)&~31; // padding

            if (bits > ctx->frame_bits)

                break;

        }

        //dprintf(ctx->m.avctx, "%d, qscale %d, bits %d, frame %d, higher %d, lower %d\n",

        //        ctx->m.avctx->frame_number, qscale, bits, ctx->frame_bits, last_higher, last_lower);

        if (bits < ctx->frame_bits) {

            if (qscale == 1)

                return 1;

            if (last_higher == qscale - 1) {

                qscale = last_higher;

                break;

            }

            last_lower = FFMIN(qscale, last_lower);

            if (last_higher != 0)

                qscale = (qscale+last_higher)>>1;

            else

                qscale -= down_step++;

            if (qscale < 1)

                qscale = 1;

            up_step = 1;

        } else {

            if (last_lower == qscale + 1)

                break;

            last_higher = FFMAX(qscale, last_higher);

            if (last_lower != INT_MAX)

                qscale = (qscale+last_lower)>>1;

            else

                qscale += up_step++;

            down_step = 1;

            if (qscale >= ctx->m.avctx->qmax)

                return -1;

        }

    }

    //dprintf(ctx->m.avctx, "out qscale %d\n", qscale);

    ctx->qscale = qscale;

    return 0;

}

static int dnxhd_rc_cmp(const void *a, const void *b)

{

    return ((const RCCMPEntry *)b)->value - ((const RCCMPEntry *)a)->value;

}

static int dnxhd_encode_fast(AVCodecContext *avctx, DNXHDEncContext *ctx)

{

    int max_bits = 0;

    int ret, x, y;

    if ((ret = dnxhd_find_qscale(ctx)) < 0)

        return -1;

    for (y = 0; y < ctx->m.mb_height; y++) {

        for (x = 0; x < ctx->m.mb_width; x++) {

            int mb = y*ctx->m.mb_width+x;

            int delta_bits;

            ctx->mb_qscale[mb] = ctx->qscale;

            ctx->mb_bits[mb] = ctx->mb_rc[ctx->qscale][mb].bits;

            max_bits += ctx->mb_rc[ctx->qscale][mb].bits;

            if (!RC_VARIANCE) {

                delta_bits = ctx->mb_rc[ctx->qscale][mb].bits-ctx->mb_rc[ctx->qscale+1][mb].bits;

                ctx->mb_cmp[mb].mb = mb;

                ctx->mb_cmp[mb].value = delta_bits ?

                    ((ctx->mb_rc[ctx->qscale][mb].ssd-ctx->mb_rc[ctx->qscale+1][mb].ssd)*100)/delta_bits

                    : INT_MIN; //avoid increasing qscale

            }

        }

        max_bits += 31; //worst padding

    }

    if (!ret) {

        if (RC_VARIANCE)

            avctx->execute(avctx, dnxhd_mb_var_thread, (void**)&ctx->thread[0], NULL, avctx->thread_count, sizeof(void*));

        qsort(ctx->mb_cmp, ctx->m.mb_num, sizeof(RCEntry), dnxhd_rc_cmp);

        for (x = 0; x < ctx->m.mb_num && max_bits > ctx->frame_bits; x++) {

            int mb = ctx->mb_cmp[x].mb;

            max_bits -= ctx->mb_rc[ctx->qscale][mb].bits - ctx->mb_rc[ctx->qscale+1][mb].bits;

            ctx->mb_qscale[mb] = ctx->qscale+1;

            ctx->mb_bits[mb] = ctx->mb_rc[ctx->qscale+1][mb].bits;

        }

    }

    return 0;

}

static void dnxhd_load_picture(DNXHDEncContext *ctx, const AVFrame *frame)

{

    int i;

    for (i = 0; i < 3; i++) {

        ctx->frame.data[i]     = frame->data[i];

        ctx->frame.linesize[i] = frame->linesize[i];

    }

    for (i = 0; i < ctx->m.avctx->thread_count; i++) {

        ctx->thread[i]->m.linesize    = ctx->frame.linesize[0]<<ctx->interlaced;

        ctx->thread[i]->m.uvlinesize  = ctx->frame.linesize[1]<<ctx->interlaced;

        ctx->thread[i]->dct_y_offset  = ctx->m.linesize  *8;

        ctx->thread[i]->dct_uv_offset = ctx->m.uvlinesize*8;

    }

    ctx->frame.interlaced_frame = frame->interlaced_frame;

    ctx->cur_field = frame->interlaced_frame && !frame->top_field_first;

}

static int dnxhd_encode_picture(AVCodecContext *avctx, unsigned char *buf, int buf_size, const void *data)

{

    DNXHDEncContext *ctx = avctx->priv_data;

    int first_field = 1;

    int offset, i, ret;

    if (buf_size < ctx->cid_table->frame_size) {

        av_log(avctx, AV_LOG_ERROR, "output buffer is too small to compress picture\n");

        return -1;

    }

    dnxhd_load_picture(ctx, data);

 encode_coding_unit:

    for (i = 0; i < 3; i++) {

        ctx->src[i] = ctx->frame.data[i];

        if (ctx->interlaced && ctx->cur_field)

            ctx->src[i] += ctx->frame.linesize[i];

    }

    dnxhd_write_header(avctx, buf);

    if (avctx->mb_decision == FF_MB_DECISION_RD)

        ret = dnxhd_encode_rdo(avctx, ctx);

    else

        ret = dnxhd_encode_fast(avctx, ctx);

    if (ret < 0) {

        av_log(avctx, AV_LOG_ERROR, "picture could not fit ratecontrol constraints\n");

        return -1;

    }

    dnxhd_setup_threads_slices(ctx, buf);

    offset = 0;

    for (i = 0; i < ctx->m.mb_height; i++) {

        AV_WB32(ctx->msip + i * 4, offset);

        offset += ctx->slice_size[i];

        assert(!(ctx->slice_size[i] & 3));

    }

    avctx->execute(avctx, dnxhd_encode_thread, (void**)&ctx->thread[0], NULL, avctx->thread_count, sizeof(void*));

    AV_WB32(buf + ctx->cid_table->coding_unit_size - 4, 0x600DC0DE); // EOF

    if (ctx->interlaced && first_field) {

        first_field     = 0;

        ctx->cur_field ^= 1;

        buf      += ctx->cid_table->coding_unit_size;

        buf_size -= ctx->cid_table->coding_unit_size;

        goto encode_coding_unit;

    }

    ctx->frame.quality = ctx->qscale*FF_QP2LAMBDA;

    return ctx->cid_table->frame_size;

}

static int dnxhd_encode_end(AVCodecContext *avctx)

{

    DNXHDEncContext *ctx = avctx->priv_data;

    int max_level = 1<<(ctx->cid_table->bit_depth+2);

    int i;

    av_free(ctx->vlc_codes-max_level*2);

    av_free(ctx->vlc_bits -max_level*2);

    av_freep(&ctx->run_codes);

    av_freep(&ctx->run_bits);

    av_freep(&ctx->mb_bits);

    av_freep(&ctx->mb_qscale);

    av_freep(&ctx->mb_rc);

    av_freep(&ctx->mb_cmp);

    av_freep(&ctx->slice_size);

    av_freep(&ctx->qmatrix_c);

    av_freep(&ctx->qmatrix_l);

    av_freep(&ctx->qmatrix_c16);

    av_freep(&ctx->qmatrix_l16);

    for (i = 1; i < avctx->thread_count; i++)

        av_freep(&ctx->thread[i]);

    return 0;

}

AVCodec dnxhd_encoder = {

    "dnxhd",

    CODEC_TYPE_VIDEO,

    CODEC_ID_DNXHD,

    sizeof(DNXHDEncContext),

    dnxhd_encode_init,

    dnxhd_encode_picture,

    dnxhd_encode_end,

    .pix_fmts = (enum PixelFormat[]){PIX_FMT_YUV422P, PIX_FMT_NONE},

    .long_name = NULL_IF_CONFIG_SMALL("VC3/DNxHD"),

};