[FFmpeg-devel] [PATCH] avcodec: add mvdv video decoder
James Almer
jamrial at gmail.com
Sat Nov 23 23:38:22 EET 2019
On 11/23/2019 5:30 PM, Paul B Mahol wrote:
> 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);
The field is 32 bits long, but the buffer you have allocated on heap is
only 524288 bytes big, so better use av_fast_mallocz instead. It will
also reduce the amount of allocated memory for most use cases with no
performance hit.
> +
> + 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 }
> };
>
>
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