[FFmpeg-devel] [PATCH 2/2] avcodec: add WinCAM Motion Video decoder
Paul B Mahol
onemda at gmail.com
Sat Aug 25 23:03:56 EEST 2018
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
configure | 1 +
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 1 +
libavcodec/avcodec.h | 1 +
libavcodec/codec_desc.c | 7 ++
libavcodec/wcmv.c | 247 ++++++++++++++++++++++++++++++++++++++++
libavformat/riff.c | 1 +
7 files changed, 259 insertions(+)
create mode 100644 libavcodec/wcmv.c
diff --git a/configure b/configure
index 0c1f6a79a7..469797935e 100755
--- a/configure
+++ b/configure
@@ -2750,6 +2750,7 @@ vp6f_decoder_select="vp6_decoder"
vp7_decoder_select="h264pred videodsp vp8dsp"
vp8_decoder_select="h264pred videodsp vp8dsp"
vp9_decoder_select="videodsp vp9_parser vp9_superframe_split_bsf"
+wcmv_decoder_deps="zlib"
webp_decoder_select="vp8_decoder exif"
wmalossless_decoder_select="llauddsp"
wmapro_decoder_select="mdct sinewin wma_freqs"
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index aee4f5431a..f8673f0121 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -677,6 +677,7 @@ OBJS-$(CONFIG_VP9_V4L2M2M_DECODER) += v4l2_m2m_dec.o
OBJS-$(CONFIG_VQA_DECODER) += vqavideo.o
OBJS-$(CONFIG_WAVPACK_DECODER) += wavpack.o
OBJS-$(CONFIG_WAVPACK_ENCODER) += wavpackenc.o
+OBJS-$(CONFIG_WCMV_DECODER) += wcmv.o
OBJS-$(CONFIG_WEBP_DECODER) += webp.o
OBJS-$(CONFIG_WEBVTT_DECODER) += webvttdec.o ass.o
OBJS-$(CONFIG_WEBVTT_ENCODER) += webvttenc.o ass_split.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index d41868c591..42d98f9b0a 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -338,6 +338,7 @@ extern AVCodec ff_vp9_v4l2m2m_decoder;
extern AVCodec ff_vqa_decoder;
extern AVCodec ff_bitpacked_decoder;
extern AVCodec ff_webp_decoder;
+extern AVCodec ff_wcmv_decoder;
extern AVCodec ff_wrapped_avframe_encoder;
extern AVCodec ff_wrapped_avframe_decoder;
extern AVCodec ff_wmv1_encoder;
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index be41b8cf0e..b6688b7af3 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -450,6 +450,7 @@ enum AVCodecID {
AV_CODEC_ID_IMM4,
AV_CODEC_ID_PROSUMER,
AV_CODEC_ID_MWSC,
+ AV_CODEC_ID_WCMV,
/* 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 129d0f1aac..46dfe3f5e5 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -1675,6 +1675,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
.long_name = NULL_IF_CONFIG_SMALL("MatchWare Screen Capture Codec"),
.props = AV_CODEC_PROP_LOSSLESS,
},
+ {
+ .id = AV_CODEC_ID_WCMV,
+ .type = AVMEDIA_TYPE_VIDEO,
+ .name = "wcmv",
+ .long_name = NULL_IF_CONFIG_SMALL("WinCAM Motion Video"),
+ .props = AV_CODEC_PROP_LOSSLESS,
+ },
/* various PCM "codecs" */
{
diff --git a/libavcodec/wcmv.c b/libavcodec/wcmv.c
new file mode 100644
index 0000000000..74cb1166bb
--- /dev/null
+++ b/libavcodec/wcmv.c
@@ -0,0 +1,247 @@
+/*
+ * WinCAM Motion Video decoder
+ *
+ * Copyright (c) 2018 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 "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+
+#include <zlib.h>
+
+typedef struct WCMVContext {
+ z_stream zstream;
+ AVFrame *prev_frame;
+ uint8_t block_data[65536*8];
+} WCMVContext;
+
+static int decode_frame(AVCodecContext *avctx,
+ void *data, int *got_frame,
+ AVPacket *avpkt)
+{
+ WCMVContext *s = avctx->priv_data;
+ AVFrame *frame = data;
+ int skip, blocks, zret, ret, intra = 0;
+ GetByteContext gb;
+ uint8_t *dst;
+
+ ret = inflateReset(&s->zstream);
+ if (ret != Z_OK) {
+ av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
+ return AVERROR_EXTERNAL;
+ }
+
+ bytestream2_init(&gb, avpkt->data, avpkt->size);
+
+ if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
+ return ret;
+
+ if (s->prev_frame->data[0]) {
+ ret = av_frame_copy(frame, s->prev_frame);
+ if (ret < 0)
+ return ret;
+ }
+
+ blocks = bytestream2_get_le16(&gb);
+ if (blocks > 5) {
+ GetByteContext bgb;
+ int x = 0, size;
+
+ if (blocks * 8 >= 0xFFFF) {
+ size = bytestream2_get_le24(&gb);
+ } else if (blocks * 8 >= 0xFF) {
+ size = bytestream2_get_le16(&gb);
+ } else {
+ size = bytestream2_get_byte(&gb);
+ }
+
+ skip = bytestream2_tell(&gb);
+ if (size > avpkt->size - skip)
+ return AVERROR_INVALIDDATA;
+
+ s->zstream.next_in = avpkt->data + skip;
+ s->zstream.avail_in = size;
+ s->zstream.next_out = s->block_data;
+ s->zstream.avail_out = sizeof(s->block_data);
+
+ zret = inflate(&s->zstream, Z_FINISH);
+ if (zret != Z_STREAM_END) {
+ av_log(avctx, AV_LOG_ERROR,
+ "Inflate failed with return code: %d.\n", zret);
+ return AVERROR_INVALIDDATA;
+ }
+
+ ret = inflateReset(&s->zstream);
+ if (ret != Z_OK) {
+ av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
+ return AVERROR_EXTERNAL;
+ }
+
+ bytestream2_skip(&gb, size);
+ bytestream2_init(&bgb, s->block_data, blocks * 8);
+
+ for (int i = 0; i < blocks; i++) {
+ int w, h;
+
+ bytestream2_skip(&bgb, 4);
+ w = bytestream2_get_le16(&bgb);
+ h = bytestream2_get_le16(&bgb);
+ x += 3 * w * h;
+ }
+
+ if (x >= 0xFFFF) {
+ bytestream2_skip(&gb, 3);
+ } else if (x >= 0xFF) {
+ bytestream2_skip(&gb, 2);
+ } else {
+ bytestream2_skip(&gb, 1);
+ }
+
+ skip = bytestream2_tell(&gb);
+
+ s->zstream.next_in = avpkt->data + skip;
+ s->zstream.avail_in = avpkt->size - skip;
+
+ bytestream2_init(&gb, s->block_data, blocks * 8);
+ } else {
+ int x = 0;
+
+ bytestream2_seek(&gb, 2, SEEK_SET);
+
+ for (int i = 0; i < blocks; i++) {
+ int w, h;
+
+ bytestream2_skip(&gb, 4);
+ w = bytestream2_get_le16(&gb);
+ h = bytestream2_get_le16(&gb);
+ x += 3 * w * h;
+ }
+
+ if (x >= 0xFFFF) {
+ bytestream2_skip(&gb, 3);
+ } else if (x >= 0xFF) {
+ bytestream2_skip(&gb, 2);
+ } else {
+ bytestream2_skip(&gb, 1);
+ }
+
+ skip = bytestream2_tell(&gb);
+
+ s->zstream.next_in = avpkt->data + skip;
+ s->zstream.avail_in = avpkt->size - skip;
+
+ bytestream2_seek(&gb, 2, SEEK_SET);
+ }
+
+ for (int block = 0; block < blocks; block++) {
+ int x, y, w, h;
+
+ x = bytestream2_get_le16(&gb);
+ y = bytestream2_get_le16(&gb);
+ w = bytestream2_get_le16(&gb);
+ h = bytestream2_get_le16(&gb);
+
+ if (blocks == 1 && x == 0 && y == 0 && w == avctx->width && h == avctx->height)
+ intra = 1;
+
+ if (x + w > avctx->width || y + h > avctx->height)
+ return AVERROR_INVALIDDATA;
+
+ if (w > avctx->width || h > avctx->height)
+ return AVERROR_INVALIDDATA;
+
+ dst = frame->data[0] + (avctx->height - y - 1) * frame->linesize[0] + x * 3;
+ for (int i = 0; i < h; i++) {
+ s->zstream.next_out = dst;
+ s->zstream.avail_out = w * 3;
+
+ zret = inflate(&s->zstream, Z_SYNC_FLUSH);
+ if (zret != Z_OK && zret != Z_STREAM_END) {
+ av_log(avctx, AV_LOG_ERROR,
+ "Inflate failed with return code: %d.\n", zret);
+ return AVERROR_INVALIDDATA;
+ }
+
+ dst -= frame->linesize[0];
+ }
+ }
+
+ frame->key_frame = intra;
+ frame->pict_type = intra ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
+
+ av_frame_unref(s->prev_frame);
+ if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
+ return ret;
+
+ *got_frame = 1;
+
+ return avpkt->size;
+}
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+ WCMVContext *s = avctx->priv_data;
+ int zret;
+
+ avctx->pix_fmt = AV_PIX_FMT_BGR24;
+
+ 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;
+ }
+
+ s->prev_frame = av_frame_alloc();
+ if (!s->prev_frame)
+ return AVERROR(ENOMEM);
+
+ return 0;
+}
+
+static av_cold int decode_close(AVCodecContext *avctx)
+{
+ WCMVContext *s = avctx->priv_data;
+
+ av_frame_free(&s->prev_frame);
+ inflateEnd(&s->zstream);
+
+ return 0;
+}
+
+AVCodec ff_wcmv_decoder = {
+ .name = "wcmv",
+ .long_name = NULL_IF_CONFIG_SMALL("WinCAM Motion Video"),
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_WCMV,
+ .priv_data_size = sizeof(WCMVContext),
+ .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,
+};
diff --git a/libavformat/riff.c b/libavformat/riff.c
index aef3c047ac..5f1aafe514 100644
--- a/libavformat/riff.c
+++ b/libavformat/riff.c
@@ -473,6 +473,7 @@ const AVCodecTag ff_codec_bmp_tags[] = {
{ AV_CODEC_ID_IMM4, MKTAG('I', 'M', 'M', '4') },
{ AV_CODEC_ID_PROSUMER, MKTAG('B', 'T', '2', '0') },
{ AV_CODEC_ID_MWSC, MKTAG('M', 'W', 'S', 'C') },
+ { AV_CODEC_ID_WCMV, MKTAG('W', 'C', 'M', 'V') },
{ AV_CODEC_ID_NONE, 0 }
};
--
2.17.1
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