[FFmpeg-devel] [PATCH] avformat: add bitpacked demuxer
lance.lmwang at gmail.com
lance.lmwang at gmail.com
Tue Dec 14 16:35:13 EET 2021
From: Limin Wang <lance.lmwang at gmail.com>
Allows user can playback bitpacked pixel format directly:
ffplay -video_size 1280x720 test.bitpacked
ffplay -f bitpacked -video_size 1280x720 -pixel_format uyvy422 test.yuv
Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
---
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/bitpackeddec.c | 136 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 138 insertions(+)
create mode 100644 libavformat/bitpackeddec.c
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 2b5caf9..90b7333 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -138,6 +138,7 @@ OBJS-$(CONFIG_BINKA_DEMUXER) += binka.o
OBJS-$(CONFIG_BINTEXT_DEMUXER) += bintext.o sauce.o
OBJS-$(CONFIG_BIT_DEMUXER) += bit.o
OBJS-$(CONFIG_BIT_MUXER) += bit.o
+OBJS-$(CONFIG_BITPACKED_DEMUXER) += bitpackeddec.o
OBJS-$(CONFIG_BMV_DEMUXER) += bmv.o
OBJS-$(CONFIG_BOA_DEMUXER) += boadec.o
OBJS-$(CONFIG_BFSTM_DEMUXER) += brstm.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 1054ac9..a100639 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -96,6 +96,7 @@ extern const AVInputFormat ff_bink_demuxer;
extern const AVInputFormat ff_binka_demuxer;
extern const AVInputFormat ff_bit_demuxer;
extern const AVOutputFormat ff_bit_muxer;
+extern const AVInputFormat ff_bitpacked_demuxer;
extern const AVInputFormat ff_bmv_demuxer;
extern const AVInputFormat ff_bfstm_demuxer;
extern const AVInputFormat ff_brstm_demuxer;
diff --git a/libavformat/bitpackeddec.c b/libavformat/bitpackeddec.c
new file mode 100644
index 0000000..ba404ad
--- /dev/null
+++ b/libavformat/bitpackeddec.c
@@ -0,0 +1,136 @@
+/*
+ * Raw bitpacked video demuxer
+ * Copyright (c) 2021 Limin Wang
+ *
+ * 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 "libavutil/imgutils.h"
+#include "libavutil/parseutils.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/opt.h"
+#include "internal.h"
+#include "avformat.h"
+
+typedef struct BitPackedDemuxerContext {
+ const AVClass *class; /**< Class for private options. */
+ int width, height; /**< Integers describing video size, set by a private option. */
+ char *pixel_format; /**< Set by a private option. */
+ AVRational framerate; /**< AVRational describing framerate, set by a private option. */
+} BitPackedDemuxerContext;
+
+static int bitpacked_read_header(AVFormatContext *ctx)
+{
+ BitPackedDemuxerContext *s = ctx->priv_data;
+ AVStream *st;
+ enum AVPixelFormat pix_fmt;
+ unsigned int pgroup; /* size of the pixel group in bytes */
+ unsigned int xinc;
+ const AVPixFmtDescriptor *desc;
+ int tag;
+ int ret;
+
+ st = avformat_new_stream(ctx, NULL);
+ if (!st)
+ return AVERROR(ENOMEM);
+
+ st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+ st->codecpar->codec_id = ctx->iformat->raw_codec_id;
+
+ if ((pix_fmt = av_get_pix_fmt(s->pixel_format)) == AV_PIX_FMT_NONE) {
+ av_log(ctx, AV_LOG_ERROR, "No such pixel format: %s.\n", s->pixel_format);
+ return AVERROR(EINVAL);
+ }
+ desc = av_pix_fmt_desc_get(pix_fmt);
+
+ ret = av_image_check_size(s->width, s->height, 0, ctx);
+ if (ret < 0)
+ return ret;
+
+ st->codecpar->width = s->width;
+ st->codecpar->height = s->height;
+ st->codecpar->format = pix_fmt;
+ st->codecpar->bits_per_coded_sample = av_get_bits_per_pixel(desc);
+
+ if (pix_fmt == AV_PIX_FMT_YUV422P10) {
+ tag = MKTAG('U', 'Y', 'V', 'Y');
+ pgroup = 5;
+ xinc = 2;
+ } else if (pix_fmt == AV_PIX_FMT_UYVY422) {
+ tag = MKTAG('U', 'Y', 'V', 'Y');
+ pgroup = 4;
+ xinc = 2;
+ pix_fmt = AV_PIX_FMT_UYVY422;
+ st->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
+ } else {
+ av_log(ctx, AV_LOG_ERROR, "unsupported the pixel format: %s yet.\n",
+ s->pixel_format);
+ return AVERROR(EINVAL);
+ }
+ st->codecpar->format = pix_fmt;
+ st->codecpar->codec_tag = tag;
+
+ avpriv_set_pts_info(st, 64, s->framerate.den, s->framerate.num);
+ ctx->packet_size = s->width * s->height * pgroup / xinc;
+ st->codecpar->bit_rate = av_rescale_q(ctx->packet_size,
+ (AVRational){8,1}, st->time_base);
+
+ return 0;
+}
+
+static int bitpacked_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ int ret;
+
+ ret = av_get_packet(s->pb, pkt, s->packet_size);
+ pkt->pts = pkt->dts = pkt->pos / s->packet_size;
+
+ pkt->stream_index = 0;
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+#define OFFSET(x) offsetof(BitPackedDemuxerContext, x)
+#define DEC AV_OPT_FLAG_DECODING_PARAM
+static const AVOption bitpacked_options[] = {
+ { "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
+ { "pixel_format", "set pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = "yuv422p10"}, 0, 0, DEC },
+ { "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC },
+ { NULL },
+};
+
+static const AVClass bitpacked_demuxer_class = {
+ .class_name = "bitpacked demuxer",
+ .item_name = av_default_item_name,
+ .option = bitpacked_options,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+#if CONFIG_BITPACKED_DEMUXER
+const AVInputFormat ff_bitpacked_demuxer = {
+ .name = "bitpacked",
+ .long_name = NULL_IF_CONFIG_SMALL("Bitpacked"),
+ .priv_data_size = sizeof(BitPackedDemuxerContext),
+ .read_header = bitpacked_read_header,
+ .read_packet = bitpacked_read_packet,
+ .flags = AVFMT_GENERIC_INDEX,
+ .extensions = "bitpacked",
+ .raw_codec_id = AV_CODEC_ID_BITPACKED,
+ .priv_class = &bitpacked_demuxer_class,
+};
+#endif // CONFIG_BITPACKED_DEMUXER
--
1.8.3.1
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