avcodec: add mvha video decoder

1 files changed, 310 insertions, 0 deletions

diff --git a/libavcodec/mvha.c b/libavcodec/mvha.c
new file mode 100644
index 0000000000..636b5e69d5
--- /dev/null
+++ b/libavcodec/mvha.c
@@ -0,0 +1,310 @@
+/*
+ * MidiVid Archive codec
+ *
+ * Copyright (c) 2019 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define CACHED_BITSTREAM_READER !ARCH_X86_32
+#include "libavutil/intreadwrite.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "get_bits.h"
+#include "internal.h"
+#include "lossless_videodsp.h"
+
+#include <zlib.h>
+
+typedef struct MVHAContext {
+    GetBitContext     gb;
+    int nb_symbols;
+
+    uint8_t           symb[256];
+    uint32_t          prob[256];
+    VLC               vlc;
+
+    z_stream          zstream;
+    LLVidDSPContext   llviddsp;
+} MVHAContext;
+
+typedef struct Node {
+    int16_t  sym;
+    int16_t  n0;
+    int16_t  l, r;
+    uint32_t count;
+} Node;
+
+static void get_tree_codes(uint32_t *bits, int16_t *lens, uint8_t *xlat,
+                           Node *nodes, int node,
+                           uint32_t pfx, int pl, int *pos)
+{
+    int s;
+
+    s = nodes[node].sym;
+    if (s != -1) {
+        bits[*pos] = (~pfx) & ((1ULL << FFMAX(pl, 1)) - 1);
+        lens[*pos] = FFMAX(pl, 1);
+        xlat[*pos] = s + (pl == 0);
+        (*pos)++;
+    } else {
+        pfx <<= 1;
+        pl++;
+        get_tree_codes(bits, lens, xlat, nodes, nodes[node].l, pfx, pl,
+                       pos);
+        pfx |= 1;
+        get_tree_codes(bits, lens, xlat, nodes, nodes[node].r, pfx, pl,
+                       pos);
+    }
+}
+
+static int build_vlc(AVCodecContext *avctx, VLC *vlc)
+{
+    MVHAContext *s = avctx->priv_data;
+    Node nodes[512];
+    uint32_t bits[256];
+    int16_t lens[256];
+    uint8_t xlat[256];
+    int cur_node, i, j, pos = 0;
+
+    ff_free_vlc(vlc);
+
+    for (i = 0; i < s->nb_symbols; i++) {
+        nodes[i].count = s->prob[i];
+        nodes[i].sym   = s->symb[i];
+        nodes[i].n0    = -2;
+        nodes[i].l     = i;
+        nodes[i].r     = i;
+    }
+
+    cur_node = s->nb_symbols;
+    j = 0;
+    do {
+        for (i = 0; ; i++) {
+            int new_node = j;
+            int first_node = cur_node;
+            int second_node = cur_node;
+            unsigned nd, st;
+
+            nodes[cur_node].count = -1;
+
+            do {
+                int val = nodes[new_node].count;
+                if (val && (val < nodes[first_node].count)) {
+                    if (val >= nodes[second_node].count) {
+                        first_node = new_node;
+                    } else {
+                        first_node = second_node;
+                        second_node = new_node;
+                    }
+                }
+                new_node += 1;
+            } while (new_node != cur_node);
+
+            if (first_node == cur_node)
+                break;
+
+            nd = nodes[second_node].count;
+            st = nodes[first_node].count;
+            nodes[second_node].count = 0;
+            nodes[first_node].count  = 0;
+            if (nd >= UINT32_MAX - st) {
+                av_log(avctx, AV_LOG_ERROR, "count overflow\n");
+                return AVERROR_INVALIDDATA;
+            }
+            nodes[cur_node].count = nd + st;
+            nodes[cur_node].sym = -1;
+            nodes[cur_node].n0 = cur_node;
+            nodes[cur_node].l = first_node;
+            nodes[cur_node].r = second_node;
+            cur_node++;
+        }
+        j++;
+    } while (cur_node - s->nb_symbols == j);
+
+    get_tree_codes(bits, lens, xlat, nodes, cur_node - 1, 0, 0, &pos);
+
+    return ff_init_vlc_sparse(vlc, 12, pos, lens, 2, 2, bits, 4, 4, xlat, 1, 1, 0);
+}
+
+static int decode_frame(AVCodecContext *avctx,
+                        void *data, int *got_frame,
+                        AVPacket *avpkt)
+{
+    MVHAContext *s = avctx->priv_data;
+    AVFrame *frame = data;
+    uint32_t type, size;
+    int ret;
+
+    if (avpkt->size <= 8)
+        return AVERROR_INVALIDDATA;
+
+    type = AV_RB32(avpkt->data);
+    size = AV_RL32(avpkt->data + 4);
+
+    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+        return ret;
+
+    if (type == MKTAG('L','Z','Y','V')) {
+        ret = inflateReset(&s->zstream);
+        if (ret != Z_OK) {
+            av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
+            return AVERROR_EXTERNAL;
+        }
+
+        s->zstream.next_in  = avpkt->data + 8;
+        s->zstream.avail_in = avpkt->size - 8;
+
+        for (int p = 0; p < 3; p++) {
+            for (int y = 0; y < avctx->height; y++) {
+                s->zstream.next_out  = frame->data[p] + (avctx->height - y - 1) * frame->linesize[p];
+                s->zstream.avail_out = avctx->width >> (p > 0);
+
+                ret = inflate(&s->zstream, Z_SYNC_FLUSH);
+                if (ret != Z_OK && ret != Z_STREAM_END) {
+                    av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
+                    return AVERROR_EXTERNAL;
+                }
+            }
+        }
+    } else if (type == MKTAG('H','U','F','Y')) {
+        GetBitContext *gb = &s->gb;
+        int first_symbol, symbol;
+
+        init_get_bits8(gb, avpkt->data + 8, avpkt->size - 8);
+
+        skip_bits(gb, 24);
+
+        first_symbol = get_bits(gb, 8);
+        s->nb_symbols = get_bits(gb, 8) + 1;
+
+        symbol = first_symbol;
+        for (int i = 0; i < s->nb_symbols; symbol++) {
+            int prob;
+
+            if (get_bits1(gb)) {
+                prob = get_bits(gb, 12);
+            } else {
+                prob = get_bits(gb, 3);
+            }
+
+            if (prob) {
+                s->symb[i] = symbol;
+                s->prob[i] = prob;
+                i++;
+            }
+        }
+
+        ret = build_vlc(avctx, &s->vlc);
+        if (ret < 0)
+            return ret;
+
+        for (int p = 0; p < 3; p++) {
+            int width = avctx->width >> (p > 0);
+            ptrdiff_t stride = frame->linesize[p];
+            uint8_t *dst;
+
+            dst = frame->data[p] + (avctx->height - 1) * frame->linesize[p];
+            for (int y = 0; y < avctx->height; y++) {
+                for (int x = 0; x < width; x++) {
+                    int v = get_vlc2(gb, s->vlc.table, s->vlc.bits, 3);
+
+                    if (v < 0)
+                        return AVERROR_INVALIDDATA;
+
+                    dst[x] = v;
+                }
+                dst -= stride;
+            }
+        }
+    } else {
+        return AVERROR_INVALIDDATA;
+    }
+
+    for (int p = 0; p < 3; p++) {
+        int left, lefttop;
+        int width = avctx->width >> (p > 0);
+        ptrdiff_t stride = frame->linesize[p];
+        uint8_t *dst;
+
+        dst = frame->data[p] + (avctx->height - 1) * frame->linesize[p];
+        s->llviddsp.add_left_pred(dst, dst, width, 0);
+        dst -= stride;
+        lefttop = left = dst[0];
+        for (int y = 1; y < avctx->height; y++) {
+            s->llviddsp.add_median_pred(dst, dst + stride, dst, width, &left, &lefttop);
+            lefttop = left = dst[0];
+            dst -= stride;
+        }
+    }
+
+    frame->pict_type = AV_PICTURE_TYPE_I;
+    frame->key_frame = 1;
+    *got_frame = 1;
+
+    return avpkt->size;
+}
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+    MVHAContext *s = avctx->priv_data;
+    int zret;
+
+    avctx->pix_fmt = AV_PIX_FMT_YUV422P;
+
+    s->zstream.zalloc = Z_NULL;
+    s->zstream.zfree = Z_NULL;
+    s->zstream.opaque = Z_NULL;
+    zret = inflateInit(&s->zstream);
+    if (zret != Z_OK) {
+        av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
+        return AVERROR_EXTERNAL;
+    }
+
+    ff_llviddsp_init(&s->llviddsp);
+
+    return 0;
+}
+
+static av_cold int decode_close(AVCodecContext *avctx)
+{
+    MVHAContext *s = avctx->priv_data;
+
+    inflateEnd(&s->zstream);
+    ff_free_vlc(&s->vlc);
+
+    return 0;
+}
+
+AVCodec ff_mvha_decoder = {
+    .name             = "mvha",
+    .long_name        = NULL_IF_CONFIG_SMALL("MidiVid Archive Codec"),
+    .type             = AVMEDIA_TYPE_VIDEO,
+    .id               = AV_CODEC_ID_MVHA,
+    .priv_data_size   = sizeof(MVHAContext),
+    .init             = decode_init,
+    .close            = decode_close,
+    .decode           = decode_frame,
+    .capabilities     = AV_CODEC_CAP_DR1,
+    .caps_internal    = FF_CODEC_CAP_INIT_THREADSAFE |
+                        FF_CODEC_CAP_INIT_CLEANUP,
+};