avcodec: add MagicYUV encoder

Signed-off-by: Paul B Mahol <onemda@gmail.com>

1 files changed, 558 insertions, 0 deletions

diff --git a/libavcodec/magicyuvenc.c b/libavcodec/magicyuvenc.c
new file mode 100644
index 0000000..f948b03
--- /dev/null
+++ b/libavcodec/magicyuvenc.c
@@ -0,0 +1,558 @@
+/*
+ * MagicYUV encoder
+ * Copyright (c) 2017 Paul B Mahol
+ *
+ * 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 <stdlib.h>
+#include <string.h>
+
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/qsort.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "put_bits.h"
+#include "internal.h"
+#include "thread.h"
+#include "lossless_videoencdsp.h"
+
+typedef enum Prediction {
+    LEFT = 1,
+    GRADIENT,
+    MEDIAN,
+} Prediction;
+
+typedef struct HuffEntry {
+    uint8_t  sym;
+    uint8_t  len;
+    uint32_t code;
+} HuffEntry;
+
+typedef struct PTable {
+    int     value;  ///< input value
+    int64_t prob;   ///< number of occurences of this value in input
+} PTable;
+
+typedef struct MagicYUVContext {
+    const AVClass       *class;
+    int                  frame_pred;
+    PutBitContext        pb;
+    int                  planes;
+    uint8_t              format;
+    AVFrame             *p;
+    int                  max;
+    int                  slice_height;
+    int                  nb_slices;
+    int                  correlate;
+    int                  hshift[4];
+    int                  vshift[4];
+    uint8_t             *slices[4];
+    unsigned             slice_pos[4];
+    unsigned             tables_size;
+    HuffEntry            he[4][256];
+    LLVidEncDSPContext   llvidencdsp;
+    void (*predict)(struct MagicYUVContext *s, uint8_t *src, uint8_t *dst,
+                    ptrdiff_t stride, int width, int height);
+} MagicYUVContext;
+
+static void left_predict(MagicYUVContext *s,
+                         uint8_t *src, uint8_t *dst, ptrdiff_t stride,
+                         int width, int height)
+{
+    uint8_t prev = 0;
+    int i, j;
+
+    for (i = 0; i < width; i++) {
+        dst[i] = src[i] - prev;
+        prev   = src[i];
+    }
+    dst += width;
+    src += stride;
+    for (j = 1; j < height; j++) {
+        prev = src[-stride];
+        for (i = 0; i < width; i++) {
+            dst[i] = src[i] - prev;
+            prev   = src[i];
+        }
+        dst += width;
+        src += stride;
+    }
+}
+
+static void gradient_predict(MagicYUVContext *s,
+                             uint8_t *src, uint8_t *dst, ptrdiff_t stride,
+                             int width, int height)
+{
+    int left = 0, top, lefttop;
+    int i, j;
+
+    for (i = 0; i < width; i++) {
+        dst[i] = src[i] - left;
+        left   = src[i];
+    }
+    dst += width;
+    src += stride;
+    for (j = 1; j < height; j++) {
+        top = src[-stride];
+        left = src[0] - top;
+        dst[0] = left;
+        for (i = 1; i < width; i++) {
+            top = src[i - stride];
+            lefttop = src[i - (stride + 1)];
+            left = src[i-1];
+            dst[i] = (src[i] - top) - left + lefttop;
+        }
+        dst += width;
+        src += stride;
+    }
+}
+
+static void median_predict(MagicYUVContext *s,
+                           uint8_t *src, uint8_t *dst, ptrdiff_t stride,
+                           int width, int height)
+{
+    int left = 0, lefttop;
+    int i, j;
+
+    for (i = 0; i < width; i++) {
+        dst[i] = src[i] - left;
+        left   = src[i];
+    }
+    dst += width;
+    src += stride;
+    for (j = 1; j < height; j++) {
+        left = lefttop = src[-stride];
+        s->llvidencdsp.sub_median_pred(dst, src - stride, src, width, &left, &lefttop);
+        dst += width;
+        src += stride;
+    }
+}
+
+static av_cold int magy_encode_init(AVCodecContext *avctx)
+{
+    MagicYUVContext *s = avctx->priv_data;
+    int i;
+
+    switch (avctx->pix_fmt) {
+    case AV_PIX_FMT_GBRP:
+        avctx->codec_tag = MKTAG('M', '8', 'R', 'G');
+        s->correlate = 1;
+        s->format = 0x65;
+        break;
+    case AV_PIX_FMT_GBRAP:
+        avctx->codec_tag = MKTAG('M', '8', 'R', 'A');
+        s->correlate = 1;
+        s->format = 0x66;
+        break;
+    case AV_PIX_FMT_YUV420P:
+        avctx->codec_tag = MKTAG('M', '8', 'Y', '0');
+        s->hshift[1] =
+        s->vshift[1] =
+        s->hshift[2] =
+        s->vshift[2] = 1;
+        s->format = 0x69;
+        break;
+    case AV_PIX_FMT_YUV422P:
+        avctx->codec_tag = MKTAG('M', '8', 'Y', '2');
+        s->hshift[1] =
+        s->hshift[2] = 1;
+        s->format = 0x68;
+        break;
+    case AV_PIX_FMT_YUV444P:
+        avctx->codec_tag = MKTAG('M', '8', 'Y', '4');
+        s->format = 0x67;
+        break;
+    case AV_PIX_FMT_YUVA444P:
+        avctx->codec_tag = MKTAG('M', '8', 'Y', 'A');
+        s->format = 0x6a;
+        break;
+    case AV_PIX_FMT_GRAY8:
+        avctx->codec_tag = MKTAG('M', '8', 'G', '0');
+        s->format = 0x6b;
+        break;
+    default:
+        av_log(avctx, AV_LOG_ERROR, "Unsupported pixel format: %d\n",
+               avctx->pix_fmt);
+        return AVERROR_INVALIDDATA;
+    }
+
+    ff_llvidencdsp_init(&s->llvidencdsp);
+
+    s->planes = av_pix_fmt_count_planes(avctx->pix_fmt);
+
+    s->nb_slices = 1;
+
+    for (i = 0; i < s->planes; i++) {
+        s->slices[i] = av_malloc(avctx->width * (avctx->height + 2) +
+                                 AV_INPUT_BUFFER_PADDING_SIZE);
+        if (!s->slices[i]) {
+            av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer.\n");
+            return AVERROR(ENOMEM);
+        }
+    }
+
+    switch (s->frame_pred) {
+    case LEFT:     s->predict = left_predict;     break;
+    case GRADIENT: s->predict = gradient_predict; break;
+    case MEDIAN:   s->predict = median_predict;   break;
+    }
+
+    return 0;
+}
+
+static int magy_huff_cmp_len(const void *a, const void *b)
+{
+    const HuffEntry *aa = a, *bb = b;
+    return (aa->len - bb->len) * 256 + aa->sym - bb->sym;
+}
+
+static int huff_cmp_sym(const void *a, const void *b)
+{
+    const HuffEntry *aa = a, *bb = b;
+    return bb->sym - aa->sym;
+}
+
+static void calculate_codes(HuffEntry *he)
+{
+    uint32_t code;
+    int i;
+
+    AV_QSORT(he, 256, HuffEntry, magy_huff_cmp_len);
+
+    code = 1;
+    for (i = 255; i >= 0; i--) {
+        he[i].code  = code >> (32 - he[i].len);
+        code       += 0x80000000u >> (he[i].len - 1);
+    }
+
+    AV_QSORT(he, 256, HuffEntry, huff_cmp_sym);
+}
+
+static void count_usage(uint8_t *src, int width,
+                        int height, PTable *counts)
+{
+    int i, j;
+
+    for (j = 0; j < height; j++) {
+        for (i = 0; i < width; i++) {
+            counts[src[i]].prob++;
+        }
+        src += width;
+    }
+}
+
+typedef struct PackageMergerList {
+    int nitems;             ///< number of items in the list and probability      ex. 4
+    int item_idx[515];      ///< index range for each item in items                   0, 2, 5, 9, 13
+    int probability[514];   ///< probability of each item                             3, 8, 18, 46
+    int items[257 * 16];    ///< chain of all individual values that make up items    A, B, A, B, C, A, B, C, D, C, D, D, E
+} PackageMergerList;
+
+static int compare_by_prob(const void *a, const void *b)
+{
+    PTable a_val = *(PTable *)a;
+    PTable b_val = *(PTable *)b;
+    return a_val.prob - b_val.prob;
+}
+
+static void magy_huffman_compute_bits(PTable *prob_table, HuffEntry *distincts,
+                                      int size, int max_length)
+{
+    PackageMergerList list_a, list_b, *to = &list_a, *from = &list_b, *temp;
+    int times, i, j, k;
+    int nbits[257] = {0};
+    int min;
+
+    av_assert0(max_length > 0);
+
+    to->nitems = 0;
+    from->nitems = 0;
+    to->item_idx[0] = 0;
+    from->item_idx[0] = 0;
+    AV_QSORT(prob_table, size, PTable, compare_by_prob);
+
+    for (times = 0; times <= max_length; times++) {
+        to->nitems = 0;
+        to->item_idx[0] = 0;
+
+        j = 0;
+        k = 0;
+
+        if (times < max_length) {
+            i = 0;
+        }
+        while (i < size || j + 1 < from->nitems) {
+            to->nitems++;
+            to->item_idx[to->nitems] = to->item_idx[to->nitems - 1];
+            if (i < size &&
+                (j + 1 >= from->nitems ||
+                 prob_table[i].prob <
+                     from->probability[j] + from->probability[j + 1])) {
+                to->items[to->item_idx[to->nitems]++] = prob_table[i].value;
+                to->probability[to->nitems - 1] = prob_table[i].prob;
+                i++;
+            } else {
+                for (k = from->item_idx[j]; k < from->item_idx[j + 2]; k++) {
+                    to->items[to->item_idx[to->nitems]++] = from->items[k];
+                }
+                to->probability[to->nitems - 1] =
+                    from->probability[j] + from->probability[j + 1];
+                j += 2;
+            }
+        }
+        temp = to;
+        to = from;
+        from = temp;
+    }
+
+    min = (size - 1 < from->nitems) ? size - 1 : from->nitems;
+    for (i = 0; i < from->item_idx[min]; i++) {
+        nbits[from->items[i]]++;
+    }
+
+    for (i = 0; i < size; i++) {
+        distincts[i].sym = i;
+        distincts[i].len = nbits[i];
+    }
+}
+
+static int encode_table(AVCodecContext *avctx, uint8_t *dst,
+                        int width, int height,
+                        PutBitContext *pb, HuffEntry *he)
+{
+    PTable counts[256] = { 0 };
+    int i;
+
+    count_usage(dst, width, height, counts);
+
+    for (i = 0; i < 256; i++) {
+        counts[i].prob++;
+        counts[i].value = i;
+    }
+
+    magy_huffman_compute_bits(counts, he, 256, 16);
+
+    calculate_codes(he);
+
+    for (i = 0; i < 256; i++) {
+        put_bits(pb, 1, 0);
+        put_bits(pb, 7, he[i].len);
+    }
+
+    return 0;
+}
+
+static int encode_slice(uint8_t *src, uint8_t *dst, int dst_size,
+                        int width, int height, HuffEntry *he, int prediction)
+{
+    PutBitContext pb;
+    int i, j;
+    int count;
+
+    init_put_bits(&pb, dst, dst_size);
+
+    put_bits(&pb, 8, 0);
+    put_bits(&pb, 8, prediction);
+
+    for (j = 0; j < height; j++) {
+        for (i = 0; i < width; i++) {
+            const int idx = src[i];
+            put_bits(&pb, he[idx].len, he[idx].code);
+        }
+
+        src += width;
+    }
+
+    count = put_bits_count(&pb) & 0x1F;
+
+    if (count)
+        put_bits(&pb, 32 - count, 0);
+
+    count = put_bits_count(&pb);
+
+    flush_put_bits(&pb);
+
+    return count >> 3;
+}
+
+static int magy_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
+                             const AVFrame *frame, int *got_packet)
+{
+    MagicYUVContext *s = avctx->priv_data;
+    PutByteContext pb;
+    const int width = avctx->width, height = avctx->height;
+    int pos, slice, i, j, ret = 0;
+
+    ret = ff_alloc_packet2(avctx, pkt, (256 + 4 * s->nb_slices + width * height) *
+                           s->planes + 256, 0);
+    if (ret < 0)
+        return ret;
+
+    bytestream2_init_writer(&pb, pkt->data, pkt->size);
+    bytestream2_put_le32(&pb, MKTAG('M', 'A', 'G', 'Y'));
+    bytestream2_put_le32(&pb, 32);
+    bytestream2_put_byte(&pb, 7);
+    bytestream2_put_byte(&pb, s->format);
+    bytestream2_put_byte(&pb, 0);
+    bytestream2_put_byte(&pb, 0);
+    bytestream2_put_le32(&pb, 0);
+
+    bytestream2_put_le32(&pb, avctx->width);
+    bytestream2_put_le32(&pb, avctx->height);
+    bytestream2_put_le32(&pb, avctx->width);
+    bytestream2_put_le32(&pb, avctx->height);
+    bytestream2_put_le32(&pb, 0);
+
+    for (i = 0; i < s->planes; i++) {
+        bytestream2_put_le32(&pb, 0);
+        for (j = 1; j < s->nb_slices; j++) {
+            bytestream2_put_le32(&pb, 0);
+        }
+    }
+
+    bytestream2_put_byte(&pb, s->planes);
+
+    for (i = 0; i < s->planes; i++) {
+        for (slice = 0; slice < s->nb_slices; slice++) {
+            bytestream2_put_byte(&pb, i);
+        }
+    }
+
+    if (s->correlate) {
+        uint8_t *r, *g, *b;
+        AVFrame *p = av_frame_clone(frame);
+
+        g = p->data[0];
+        b = p->data[1];
+        r = p->data[2];
+
+        for (i = 0; i < height; i++) {
+            s->llvidencdsp.diff_bytes(b, b, g, width);
+            s->llvidencdsp.diff_bytes(r, r, g, width);
+            g += p->linesize[0];
+            b += p->linesize[1];
+            r += p->linesize[2];
+        }
+
+        FFSWAP(uint8_t*, p->data[0], p->data[1]);
+        FFSWAP(int, p->linesize[0], p->linesize[1]);
+
+        for (i = 0; i < s->planes; i++) {
+            for (slice = 0; slice < s->nb_slices; slice++) {
+                s->predict(s, p->data[i], s->slices[i], p->linesize[i],
+                               p->width, p->height);
+            }
+        }
+
+        av_frame_free(&p);
+    } else {
+        for (i = 0; i < s->planes; i++) {
+            for (slice = 0; slice < s->nb_slices; slice++) {
+                s->predict(s, frame->data[i], s->slices[i], frame->linesize[i],
+                           AV_CEIL_RSHIFT(frame->width, s->hshift[i]),
+                           AV_CEIL_RSHIFT(frame->height, s->vshift[i]));
+            }
+        }
+    }
+
+    init_put_bits(&s->pb, pkt->data + bytestream2_tell_p(&pb), bytestream2_get_bytes_left_p(&pb));
+
+    for (i = 0; i < s->planes; i++) {
+        encode_table(avctx, s->slices[i],
+                     AV_CEIL_RSHIFT(frame->width,  s->hshift[i]),
+                     AV_CEIL_RSHIFT(frame->height, s->vshift[i]),
+                     &s->pb, s->he[i]);
+    }
+    s->tables_size = (put_bits_count(&s->pb) + 7) >> 3;
+    bytestream2_skip_p(&pb, s->tables_size);
+
+    for (i = 0; i < s->planes; i++) {
+        unsigned slice_size;
+
+        s->slice_pos[i] = bytestream2_tell_p(&pb);
+        slice_size = encode_slice(s->slices[i], pkt->data + bytestream2_tell_p(&pb),
+                                  bytestream2_get_bytes_left_p(&pb),
+                                  AV_CEIL_RSHIFT(frame->width,  s->hshift[i]),
+                                  AV_CEIL_RSHIFT(frame->height, s->vshift[i]),
+                                  s->he[i], s->frame_pred);
+        bytestream2_skip_p(&pb, slice_size);
+    }
+
+    pos = bytestream2_tell_p(&pb);
+    bytestream2_seek_p(&pb, 32, SEEK_SET);
+    bytestream2_put_le32(&pb, s->slice_pos[0] - 32);
+    for (i = 0; i < s->planes; i++) {
+        bytestream2_put_le32(&pb, s->slice_pos[i] - 32);
+    }
+    bytestream2_seek_p(&pb, pos, SEEK_SET);
+
+    pkt->size   = bytestream2_tell_p(&pb);
+    pkt->flags |= AV_PKT_FLAG_KEY;
+
+    *got_packet = 1;
+
+    return 0;
+}
+
+static av_cold int magy_encode_close(AVCodecContext *avctx)
+{
+    MagicYUVContext *s = avctx->priv_data;
+    int i;
+
+    for (i = 0; i < s->planes; i++)
+        av_freep(&s->slices[i]);
+
+    return 0;
+}
+
+#define OFFSET(x) offsetof(MagicYUVContext, x)
+#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
+static const AVOption options[] = {
+    { "pred", "Prediction method", OFFSET(frame_pred), AV_OPT_TYPE_INT, {.i64=LEFT}, LEFT, MEDIAN, VE, "pred" },
+    { "left",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = LEFT },     0, 0, VE, "pred" },
+    { "gradient", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = GRADIENT }, 0, 0, VE, "pred" },
+    { "median",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = MEDIAN },   0, 0, VE, "pred" },
+    { NULL},
+};
+
+static const AVClass magicyuv_class = {
+    .class_name = "magicyuv",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+AVCodec ff_magicyuv_encoder = {
+    .name             = "magicyuv",
+    .long_name        = NULL_IF_CONFIG_SMALL("MagicYUV video"),
+    .type             = AVMEDIA_TYPE_VIDEO,
+    .id               = AV_CODEC_ID_MAGICYUV,
+    .priv_data_size   = sizeof(MagicYUVContext),
+    .priv_class       = &magicyuv_class,
+    .init             = magy_encode_init,
+    .close            = magy_encode_close,
+    .encode2          = magy_encode_frame,
+    .capabilities     = AV_CODEC_CAP_FRAME_THREADS | AV_CODEC_CAP_INTRA_ONLY,
+    .pix_fmts         = (const enum AVPixelFormat[]) {
+                          AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, AV_PIX_FMT_YUV422P,
+                          AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVA444P, AV_PIX_FMT_GRAY8,
+                          AV_PIX_FMT_NONE
+                      },
+};