[FFmpeg-devel] [PATCH] avcodec: add mvdv video decoder
Paul B Mahol
onemda at gmail.com
Sat Nov 23 22:30:53 EET 2019
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 1 +
libavcodec/avcodec.h | 1 +
libavcodec/codec_desc.c | 7 ++
libavcodec/midivid.c | 264 ++++++++++++++++++++++++++++++++++++++++
libavformat/riff.c | 1 +
6 files changed, 275 insertions(+)
create mode 100644 libavcodec/midivid.c
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 006a472a6d..52e5b4f345 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -493,6 +493,7 @@ OBJS-$(CONFIG_MSZH_DECODER) += lcldec.o
OBJS-$(CONFIG_MTS2_DECODER) += mss4.o
OBJS-$(CONFIG_MVC1_DECODER) += mvcdec.o
OBJS-$(CONFIG_MVC2_DECODER) += mvcdec.o
+OBJS-$(CONFIG_MVDV_DECODER) += midivid.o
OBJS-$(CONFIG_MWSC_DECODER) += mwsc.o
OBJS-$(CONFIG_MXPEG_DECODER) += mxpegdec.o
OBJS-$(CONFIG_NELLYMOSER_DECODER) += nellymoserdec.o nellymoser.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 0c0741936c..4eb1afbea1 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -218,6 +218,7 @@ extern AVCodec ff_mszh_decoder;
extern AVCodec ff_mts2_decoder;
extern AVCodec ff_mvc1_decoder;
extern AVCodec ff_mvc2_decoder;
+extern AVCodec ff_mvdv_decoder;
extern AVCodec ff_mwsc_decoder;
extern AVCodec ff_mxpeg_decoder;
extern AVCodec ff_nuv_decoder;
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 813a43b72e..1cbc9c9ef1 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -458,6 +458,7 @@ enum AVCodecID {
AV_CODEC_ID_LSCR,
AV_CODEC_ID_VP4,
AV_CODEC_ID_IMM5,
+ AV_CODEC_ID_MVDV,
/* various PCM "codecs" */
AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 5961af3c85..3e634bbec7 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -1733,6 +1733,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
.long_name = NULL_IF_CONFIG_SMALL("Infinity IMM5"),
.props = AV_CODEC_PROP_LOSSY,
},
+ {
+ .id = AV_CODEC_ID_MVDV,
+ .type = AVMEDIA_TYPE_VIDEO,
+ .name = "mvdv",
+ .long_name = NULL_IF_CONFIG_SMALL("MidiVid VQ"),
+ .props = AV_CODEC_PROP_LOSSY,
+ },
/* various PCM "codecs" */
{
diff --git a/libavcodec/midivid.c b/libavcodec/midivid.c
new file mode 100644
index 0000000000..f2d125f2cf
--- /dev/null
+++ b/libavcodec/midivid.c
@@ -0,0 +1,264 @@
+/*
+ * MidiVid decoder
+ * 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>
+
+#include "libavutil/imgutils.h"
+#include "libavutil/internal.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/mem.h"
+
+#define BITSTREAM_READER_LE
+#include "avcodec.h"
+#include "get_bits.h"
+#include "bytestream.h"
+#include "internal.h"
+
+typedef struct MidiVidContext {
+ GetByteContext gb;
+
+ uint8_t uncompressed[524288];
+ uint8_t *skip;
+
+ AVFrame *frame;
+} MidiVidContext;
+
+static int decode_mvdv(MidiVidContext *s, AVCodecContext *avctx, AVFrame *frame)
+{
+ GetByteContext *gb = &s->gb;
+ GetBitContext mask;
+ GetByteContext idx9;
+ uint16_t nb_vectors, intra_flag;
+ const uint8_t *vec;
+ const uint8_t *mask_start;
+ uint8_t *skip;
+ int mask_size;
+ int idx9bits = 0;
+ int idx9val = 0;
+ int num_blocks;
+
+ nb_vectors = bytestream2_get_le16(gb);
+ intra_flag = bytestream2_get_le16(gb);
+ if (intra_flag) {
+ num_blocks = (avctx->width / 2) * (avctx->height / 2);
+ } else {
+ int skip_linesize;
+
+ num_blocks = bytestream2_get_le32(gb);
+ skip_linesize = avctx->width >> 1;
+ mask_start = gb->buffer_start + bytestream2_tell(gb);
+ mask_size = (avctx->width >> 5) * (avctx->height >> 2);
+ init_get_bits8(&mask, mask_start, mask_size);
+ bytestream2_skip(gb, mask_size);
+ skip = s->skip;
+
+ for (int y = 0; y < avctx->height >> 2; y++) {
+ for (int x = 0; x < avctx->width >> 2; x++) {
+ int flag = !get_bits1(&mask);
+
+ skip[(y*2) *skip_linesize + x*2 ] = flag;
+ skip[(y*2) *skip_linesize + x*2+1] = flag;
+ skip[(y*2+1)*skip_linesize + x*2 ] = flag;
+ skip[(y*2+1)*skip_linesize + x*2+1] = flag;
+ }
+ }
+ }
+
+ vec = gb->buffer_start + bytestream2_tell(gb);
+ if (bytestream2_get_bytes_left(gb) < nb_vectors * 12)
+ return AVERROR_INVALIDDATA;
+ bytestream2_skip(gb, nb_vectors * 12);
+ if (nb_vectors > 256) {
+ if (bytestream2_get_bytes_left(gb) < (num_blocks + 7) / 8)
+ return AVERROR_INVALIDDATA;
+ bytestream2_init(&idx9, gb->buffer_start + bytestream2_tell(gb), (num_blocks + 7) / 8);
+ bytestream2_skip(gb, (num_blocks + 7) / 8);
+ }
+
+ skip = s->skip;
+
+ for (int y = avctx->height - 2; y >= 0; y -= 2) {
+ uint8_t *dsty = frame->data[0] + y * frame->linesize[0];
+ uint8_t *dstu = frame->data[1] + y * frame->linesize[1];
+ uint8_t *dstv = frame->data[2] + y * frame->linesize[2];
+
+ for (int x = 0; x < avctx->width; x += 2) {
+ int idx;
+
+ if (!intra_flag && *skip++)
+ continue;
+ if (bytestream2_get_bytes_left(gb) <= 0)
+ return AVERROR_INVALIDDATA;
+ if (nb_vectors <= 256) {
+ idx = bytestream2_get_byte(gb);
+ } else {
+ if (idx9bits == 0) {
+ idx9val = bytestream2_get_byte(&idx9);
+ idx9bits = 8;
+ }
+ idx9bits--;
+ idx = bytestream2_get_byte(gb) | (((idx9val >> (7 - idx9bits)) & 1) << 8);
+ }
+
+ dsty[x +frame->linesize[0]] = vec[idx * 12 + 0];
+ dsty[x+1+frame->linesize[0]] = vec[idx * 12 + 3];
+ dsty[x] = vec[idx * 12 + 6];
+ dsty[x+1] = vec[idx * 12 + 9];
+
+ dstu[x +frame->linesize[1]] = vec[idx * 12 + 1];
+ dstu[x+1+frame->linesize[1]] = vec[idx * 12 + 4];
+ dstu[x] = vec[idx * 12 + 7];
+ dstu[x+1] = vec[idx * 12 +10];
+
+ dstv[x +frame->linesize[2]] = vec[idx * 12 + 2];
+ dstv[x+1+frame->linesize[2]] = vec[idx * 12 + 5];
+ dstv[x] = vec[idx * 12 + 8];
+ dstv[x+1] = vec[idx * 12 +11];
+ }
+ }
+
+ return intra_flag;
+}
+
+static int lzss_uncompress(MidiVidContext *s, GetByteContext *gb, uint8_t *dst, int size)
+{
+ uint8_t *dst_start = dst;
+ uint8_t *dst_end = dst + size;
+
+ for (;bytestream2_get_bytes_left(gb) > 0;) {
+ int op = bytestream2_get_le16(gb);
+
+ for (int i = 0; i < 16; i++) {
+ if (op & 1) {
+ int s0 = bytestream2_get_byte(gb);
+ int s1 = bytestream2_get_byte(gb);
+ int offset = ((s0 & 0xF0) << 4) | s1;
+ int length = (s0 & 0xF) + 3;
+
+ if (dst + length >= dst_end ||
+ dst - offset < dst_start)
+ return AVERROR_INVALIDDATA;
+ for (int j = 0; j < length; j++) {
+ dst[j] = dst[j - offset];
+ }
+ dst += length;
+ } else {
+ if (dst >= dst_end)
+ return AVERROR_INVALIDDATA;
+ *dst++ = bytestream2_get_byte(gb);
+ }
+ op >>= 1;
+ }
+ }
+
+ return 0;
+}
+
+static int decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame, AVPacket *avpkt)
+{
+ MidiVidContext *s = avctx->priv_data;
+ GetByteContext *gb = &s->gb;
+ AVFrame *frame = s->frame;
+ int ret, key, uncompressed;
+
+ if (avpkt->size <= 12)
+ return AVERROR_INVALIDDATA;
+
+ bytestream2_init(gb, avpkt->data, avpkt->size);
+ bytestream2_skip(gb, 8);
+ uncompressed = bytestream2_get_le32(gb);
+
+ if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
+ return ret;
+
+ if (uncompressed) {
+ ret = decode_mvdv(s, avctx, frame);
+ } else {
+ ret = lzss_uncompress(s, gb, s->uncompressed, sizeof(s->uncompressed));
+ if (ret < 0)
+ return ret;
+ bytestream2_init(gb, s->uncompressed, sizeof(s->uncompressed));
+ ret = decode_mvdv(s, avctx, frame);
+ }
+
+ if (ret < 0)
+ return ret;
+ key = ret;
+
+ if ((ret = av_frame_ref(data, s->frame)) < 0)
+ return ret;
+
+ frame->pict_type = key ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
+ frame->key_frame = key;
+ *got_frame = 1;
+
+ return avpkt->size;
+}
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+ MidiVidContext *s = avctx->priv_data;
+
+ avctx->pix_fmt = AV_PIX_FMT_YUV444P;
+
+ s->frame = av_frame_alloc();
+ if (!s->frame)
+ return AVERROR(ENOMEM);
+ s->skip = av_calloc(avctx->width >> 1, avctx->height >> 1);
+ if (!s->skip)
+ return AVERROR(ENOMEM);
+
+ return 0;
+}
+
+static void decode_flush(AVCodecContext *avctx)
+{
+ MidiVidContext *s = avctx->priv_data;
+
+ av_frame_unref(s->frame);
+}
+
+static av_cold int decode_close(AVCodecContext *avctx)
+{
+ MidiVidContext *s = avctx->priv_data;
+
+ av_frame_free(&s->frame);
+ av_freep(&s->skip);
+
+ return 0;
+}
+
+AVCodec ff_mvdv_decoder = {
+ .name = "mvdv",
+ .long_name = NULL_IF_CONFIG_SMALL("MidiVid VQ"),
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_MVDV,
+ .priv_data_size = sizeof(MidiVidContext),
+ .init = decode_init,
+ .decode = decode_frame,
+ .flush = decode_flush,
+ .close = decode_close,
+ .capabilities = AV_CODEC_CAP_DR1,
+ .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
+};
diff --git a/libavformat/riff.c b/libavformat/riff.c
index 048a79e394..25ccedc8ce 100644
--- a/libavformat/riff.c
+++ b/libavformat/riff.c
@@ -489,6 +489,7 @@ const AVCodecTag ff_codec_bmp_tags[] = {
{ AV_CODEC_ID_AGM, MKTAG('A', 'G', 'M', '7') },
{ AV_CODEC_ID_LSCR, MKTAG('L', 'S', 'C', 'R') },
{ AV_CODEC_ID_IMM5, MKTAG('I', 'M', 'M', '5') },
+ { AV_CODEC_ID_MVDV, MKTAG('M', 'V', 'D', 'V') },
{ AV_CODEC_ID_NONE, 0 }
};
--
2.17.1
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