DNxHD (SMPTE VC-3) encoder

Originally committed as revision 10682 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 845 insertions, 0 deletions

diff --git a/libavcodec/dnxhdenc.c b/libavcodec/dnxhdenc.c
new file mode 100644
index 0000000000..0198b31a9f
--- /dev/null
+++ b/libavcodec/dnxhdenc.c
@@ -0,0 +1,845 @@
+/*
+ * 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 "dnxhddata.h"
+
+typedef struct {
+    uint16_t mb;
+    int value;
+} RCCMPEntry;
+
+typedef struct {
+    int ssd;
+    int bits;
+} RCEntry;
+
+int dct_quantize_c(MpegEncContext *s, DCTELEM *block, int n, int qscale, int *overflow);
+
+typedef struct DNXHDEncContext {
+    MpegEncContext m; ///< Used for quantization dsp functions
+
+    AVFrame frame;
+    int cid;
+    const CIDEntry *cid_table;
+    uint8_t *msip; ///< Macroblock Scan Indices Payload
+    uint32_t *slice_size;
+
+    struct DNXHDEncContext *thread[MAX_THREADS];
+
+    unsigned dct_y_offset;
+    unsigned dct_uv_offset;
+    int interlaced;
+    int cur_field;
+
+    DECLARE_ALIGNED_16(DCTELEM, blocks[8][64]);
+
+    int      (*qmatrix_c)     [64];
+    int      (*qmatrix_l)     [64];
+    uint16_t (*qmatrix_l16)[2][64];
+    uint16_t (*qmatrix_c16)[2][64];
+
+    unsigned frame_bits;
+    uint8_t *src[3];
+
+    uint16_t *table_vlc_codes;
+    uint8_t  *table_vlc_bits;
+    uint16_t *table_run_codes;
+    uint8_t  *table_run_bits;
+
+    /** Rate control */
+    unsigned slice_bits;
+    unsigned qscale;
+    unsigned lambda;
+
+    unsigned thread_size;
+
+    uint16_t *mb_bits;
+    uint8_t  *mb_qscale;
+
+    RCCMPEntry *mb_cmp;
+    RCEntry   (*mb_rc)[8160];
+} DNXHDEncContext;
+
+#define LAMBDA_FRAC_BITS 10
+
+static int dnxhd_init_vlc(DNXHDEncContext *ctx)
+{
+    int i;
+
+    CHECKED_ALLOCZ(ctx->table_vlc_codes, 449*2);
+    CHECKED_ALLOCZ(ctx->table_vlc_bits,    449);
+    CHECKED_ALLOCZ(ctx->table_run_codes,  63*2);
+    CHECKED_ALLOCZ(ctx->table_run_bits,     63);
+
+    for (i = 0; i < 257; i++) {
+        int level = ctx->cid_table->ac_level[i] +
+            (ctx->cid_table->ac_run_flag[i] << 7) + (ctx->cid_table->ac_index_flag[i] << 8);
+        assert(level < 449);
+        if (ctx->cid_table->ac_level[i] == 64 && ctx->cid_table->ac_index_flag[i])
+            level -= 64; // use 0+(1<<8) level
+        ctx->table_vlc_codes[level] = ctx->cid_table->ac_codes[i];
+        ctx->table_vlc_bits [level] = ctx->cid_table->ac_bits[i];
+    }
+    for (i = 0; i < 62; i++) {
+        int run = ctx->cid_table->run[i];
+        assert(run < 63);
+        ctx->table_run_codes[run] = ctx->cid_table->run_codes[i];
+        ctx->table_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_weigth[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_weigth[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;
+
+    if (avctx->flags & CODEC_FLAG_INTERLACED_DCT) {
+        if      (avctx->bit_rate == 120000000)
+            ctx->cid = 1242;
+        else if (avctx->bit_rate == 185000000)
+            ctx->cid = 1243;
+    } else {
+        if      (avctx->bit_rate == 120000000)
+            ctx->cid = 1237;
+        else if (avctx->bit_rate == 185000000)
+            ctx->cid = 1238;
+    }
+    if (!ctx->cid || avctx->width != 1920 || avctx->height != 1080 || avctx->pix_fmt != PIX_FMT_YUV422P) {
+        av_log(avctx, AV_LOG_ERROR, "video parameters incompatible with DNxHD\n");
+        return -1;
+    }
+
+    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 offset = 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 sign;
+            MASK_ABS(sign, slevel);
+            if (slevel > 64) {
+                offset = (slevel-1) >> 6;
+                slevel = 256 | (slevel & 63); // level 64 is treated as 0
+            }
+            if (run_level)
+                slevel |= 128;
+            put_bits(&ctx->m.pb, ctx->table_vlc_bits[slevel]+1, (ctx->table_vlc_codes[slevel]<<1)|(sign&1));
+            if (offset) {
+                put_bits(&ctx->m.pb, 4, offset);
+                offset = 0;
+            }
+            if (run_level)
+                put_bits(&ctx->m.pb, ctx->table_run_bits[run_level], ctx->table_run_codes[run_level]);
+            last_non_zero = i;
+        }
+    }
+    put_bits(&ctx->m.pb, ctx->table_vlc_bits[0], ctx->table_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 *weigth_matrix;
+    int level;
+    int i;
+
+    weigth_matrix = (n&2) ? ctx->cid_table->chroma_weigth : ctx->cid_table->luma_weigth;
+
+    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 * weigth_matrix[i];
+                if (weigth_matrix[i] != 32)
+                    level += 32;
+                level >>= 6;
+                level = -level;
+            } else {
+                level = (2*level+1) * qscale * weigth_matrix[i];
+                if (weigth_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;
+            level = FFABS(level);
+            if (level > 64) {
+                level = 256 | (level & 63); // level 64 is treated as 0
+                bits += 4;
+            }
+            level |= (!!run_level)<<7;
+            bits += ctx->table_vlc_bits[level]+1 + ctx->table_run_bits[run_level];
+            last_non_zero = i;
+        }
+    }
+    return bits;
+}
+
+static av_always_inline void dnxhd_get_pixels_4x8(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 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) {
+        if (ctx->interlaced) {
+            dnxhd_get_pixels_4x8(ctx->blocks[4], ptr_y + ctx->dct_y_offset    , ctx->m.linesize);
+            dnxhd_get_pixels_4x8(ctx->blocks[5], ptr_y + ctx->dct_y_offset + 8, ctx->m.linesize);
+            dnxhd_get_pixels_4x8(ctx->blocks[6], ptr_u + ctx->dct_uv_offset   , ctx->m.uvlinesize);
+            dnxhd_get_pixels_4x8(ctx->blocks[7], ptr_v + ctx->dct_uv_offset   , ctx->m.uvlinesize);
+        } else
+            memset(ctx->blocks[4], 0, 4*64*sizeof(DCTELEM));
+    } 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 = 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->table_vlc_bits[0];
+        }
+    }
+    return 0;
+}
+
+static int dnxhd_encode_thread(AVCodecContext *avctx, void *arg)
+{
+    DNXHDEncContext *ctx = 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);
+                dnxhd_encode_block(ctx, block, last_index, n);
+            }
+        }
+        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 = 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)
+{
+    unsigned lambda, up_lambda, down_lambda;
+    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);
+    }
+    up_lambda = avctx->qmax<<LAMBDA_FRAC_BITS;
+    down_lambda = 1; // higher ?
+    lambda = ctx->lambda;
+
+    for (;;) {
+        int bits = 0;
+        int end = 0;
+        if (lambda == up_lambda) {
+            lambda--;
+            end = 1; // need to set final qscales/bits
+        }
+        if (lambda == down_lambda) {
+            lambda++;
+            end = 1;
+        }
+        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 %d, down %d, bits %d, frame %d\n", lambda, up_lambda, down_lambda, bits, ctx->frame_bits);
+        if (end) {
+            if (bits > ctx->frame_bits)
+                return -1;
+            break;
+        }
+        if (bits < ctx->frame_bits) {
+            up_lambda = lambda;
+            lambda = (down_lambda+lambda)>>1;
+        } else {
+            down_lambda = lambda;
+            lambda = (up_lambda+lambda)>>1;
+        }
+    }
+    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);
+        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)
+                break;
+            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 ((RCCMPEntry *)b)->value - ((RCCMPEntry *)a)->value;
+}
+
+static int dnxhd_encode_variance(AVCodecContext *avctx, DNXHDEncContext *ctx)
+{
+    int max_bits = 0;
+    int x, y;
+    if (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 (max_bits > ctx->frame_bits) {
+        if (RC_VARIANCE)
+            avctx->execute(avctx, dnxhd_mb_var_thread, (void**)&ctx->thread[0], NULL, avctx->thread_count);
+        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, 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, 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_variance(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);
+
+    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;
+    }
+
+    return ctx->cid_table->frame_size;
+}
+
+static int dnxhd_encode_end(AVCodecContext *avctx)
+{
+    DNXHDEncContext *ctx = avctx->priv_data;
+    int i;
+
+    av_freep(&ctx->table_vlc_codes);
+    av_freep(&ctx->table_vlc_bits);
+    av_freep(&ctx->table_run_codes);
+    av_freep(&ctx->table_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, -1},
+};