[FFmpeg-devel] [PATCH 4/4][VERSION 2] avformat: add moflex demuxer
Paul B Mahol
onemda at gmail.com
Sat Aug 29 14:36:21 EEST 2020
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/moflex.c | 358 +++++++++++++++++++++++++++++++++++++++
3 files changed, 360 insertions(+)
create mode 100644 libavformat/moflex.c
diff --git a/libavformat/Makefile b/libavformat/Makefile
index cbb33fe37c..1e0ac317e5 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -319,6 +319,7 @@ OBJS-$(CONFIG_MLV_DEMUXER) += mlvdec.o riffdec.o
OBJS-$(CONFIG_MM_DEMUXER) += mm.o
OBJS-$(CONFIG_MMF_DEMUXER) += mmf.o
OBJS-$(CONFIG_MMF_MUXER) += mmf.o rawenc.o
+OBJS-$(CONFIG_MOFLEX_DEMUXER) += moflex.o
OBJS-$(CONFIG_MOV_DEMUXER) += mov.o mov_chan.o mov_esds.o replaygain.o
OBJS-$(CONFIG_MOV_MUXER) += movenc.o av1.o avc.o hevc.o vpcc.o \
movenchint.o mov_chan.o rtp.o \
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 0aa9dd7198..28331facb9 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -249,6 +249,7 @@ extern AVInputFormat ff_mlv_demuxer;
extern AVInputFormat ff_mm_demuxer;
extern AVInputFormat ff_mmf_demuxer;
extern AVOutputFormat ff_mmf_muxer;
+extern AVInputFormat ff_moflex_demuxer;
extern AVInputFormat ff_mov_demuxer;
extern AVOutputFormat ff_mov_muxer;
extern AVOutputFormat ff_mp2_muxer;
diff --git a/libavformat/moflex.c b/libavformat/moflex.c
new file mode 100644
index 0000000000..3761837895
--- /dev/null
+++ b/libavformat/moflex.c
@@ -0,0 +1,358 @@
+/*
+ * MOFLEX demuxer
+ * Copyright (c) 2020 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 "libavcodec/bytestream.h"
+
+#include "avformat.h"
+#include "internal.h"
+
+typedef struct BitReader {
+ unsigned last;
+ unsigned pos;
+} BitReader;
+
+typedef struct MOFLEXDemuxContext {
+ unsigned size;
+ int64_t pos;
+ int64_t ts;
+ int flags;
+ int in_block;
+
+ BitReader br;
+} MOFLEXDemuxContext;
+
+static int pop(BitReader *br, AVIOContext *pb)
+{
+ if (avio_feof(pb))
+ return AVERROR_EOF;
+
+ if ((br->pos & 7) == 0)
+ br->last = (unsigned)avio_r8(pb) << 24U;
+ else
+ br->last <<= 1;
+
+ br->pos++;
+ return !!(br->last & 0x80000000);
+}
+
+static int pop_int(BitReader *br, AVIOContext *pb, int n)
+{
+ int value = 0;
+
+ for (int i = 0; i < n; i++) {
+ int ret = pop(br, pb);
+
+ if (ret < 0)
+ return ret;
+ value = 2 * value + ret;
+ }
+
+ return value;
+}
+
+static int pop_length(BitReader *br, AVIOContext *pb)
+{
+ int ret, n = 1;
+
+ while ((ret = pop(br, pb)) == 0)
+ n++;
+
+ if (ret < 0)
+ return ret;
+ return n;
+}
+
+static int read_var_byte(AVFormatContext *s, unsigned *out)
+{
+ AVIOContext *pb = s->pb;
+ unsigned value = 0, data;
+
+ data = avio_r8(pb);
+ if (!(data & 0x80)) {
+ *out = data;
+ return 0;
+ }
+
+ value = (data & 0x7F) << 7;
+ data = avio_r8(pb);
+ if (!(data & 0x80)) {
+ value |= data;
+ *out = value;
+ return 0;
+ }
+
+ value = ((data & 0x7F) | value) << 7;
+ data = avio_r8(pb);
+ if (!(data & 0x80)) {
+ value |= data;
+ *out = value;
+ return 0;
+ }
+
+ value = (((data & 0x7F) | value) << 7) | avio_r8(pb);
+ *out = value;
+
+ return 0;
+}
+
+static int moflex_probe(const AVProbeData *p)
+{
+ GetByteContext gb;
+ int score = 0;
+
+ bytestream2_init(&gb, p->buf, p->buf_size);
+
+ if (bytestream2_get_be16(&gb) != 0x4C32)
+ return 0;
+ score += 10;
+
+ bytestream2_skip(&gb, 10);
+ if (bytestream2_get_be16(&gb) == 0)
+ return 0;
+ score += 5;
+
+ while (bytestream2_get_bytes_left(&gb) > 0) {
+ int type = bytestream2_get_byte(&gb);
+ int size = bytestream2_get_byte(&gb);
+
+ if (type == 0) {
+ score += 5 * (size == 0);
+ break;
+ }
+ if ((type == 1 && size == 12) ||
+ (type == 2 && size == 6) ||
+ (type == 3 && size == 13) ||
+ (type == 4 && size == 2))
+ score += 20;
+ bytestream2_skip(&gb, size);
+ }
+
+ return FFMIN(AVPROBE_SCORE_MAX, score);
+}
+
+static int moflex_read_sync(AVFormatContext *s)
+{
+ MOFLEXDemuxContext *m = s->priv_data;
+ AVIOContext *pb = s->pb;
+
+ if (avio_rb16(pb) != 0x4C32) {
+ avio_seek(pb, -2, SEEK_CUR);
+ return 1;
+ }
+
+ avio_skip(pb, 2);
+ m->ts = avio_rb64(pb);
+ m->size = avio_rb16(pb) + 1;
+
+ while (!avio_feof(pb)) {
+ unsigned type, ssize, codec_id = 0;
+ unsigned codec_type, width = 0, height = 0, sample_rate = 0, channels = 0;
+ int stream_index = -1;
+ int format;
+ AVRational fps;
+
+ read_var_byte(s, &type);
+ read_var_byte(s, &ssize);
+
+ switch (type) {
+ case 0:
+ if (ssize > 0)
+ avio_skip(pb, ssize);
+ return 0;
+ case 2:
+ codec_type = AVMEDIA_TYPE_AUDIO;
+ stream_index = avio_r8(pb);
+ codec_id = avio_r8(pb);
+ switch (codec_id) {
+ case 0: codec_id = AV_CODEC_ID_FASTAUDIO; break;
+ case 1: codec_id = AV_CODEC_ID_ADPCM_IMA_MOFLEX; break;
+ case 2: codec_id = AV_CODEC_ID_PCM_S16LE; break;
+ default:
+ av_log(s, AV_LOG_ERROR, "Unsupported audio codec: %d\n", codec_id);
+ return AVERROR_PATCHWELCOME;
+ }
+ sample_rate = avio_rb24(pb) + 1;
+ channels = avio_r8(pb) + 1;
+ break;
+ case 1:
+ case 3:
+ codec_type = AVMEDIA_TYPE_VIDEO;
+ stream_index = avio_r8(pb);
+ codec_id = avio_r8(pb);
+ switch (codec_id) {
+ case 0: codec_id = AV_CODEC_ID_MOBICLIP; break;
+ default:
+ av_log(s, AV_LOG_ERROR, "Unsupported video codec: %d\n", codec_id);
+ return AVERROR_PATCHWELCOME;
+ }
+ fps.num = avio_rb16(pb);
+ fps.den = avio_rb16(pb);
+ width = avio_rb16(pb);
+ height = avio_rb16(pb);
+ format = AV_PIX_FMT_YUV420P;
+ avio_skip(pb, type == 3 ? 3 : 2);
+ break;
+ case 4:
+ codec_type = AVMEDIA_TYPE_DATA;
+ stream_index = avio_r8(pb);
+ avio_skip(pb, 1);
+ break;
+ }
+
+ if (stream_index == s->nb_streams) {
+ AVStream *st = avformat_new_stream(s, NULL);
+
+ if (!st)
+ return AVERROR(ENOMEM);
+
+ st->codecpar->codec_type = codec_type;
+ st->codecpar->codec_id = codec_id;
+ st->codecpar->width = width;
+ st->codecpar->height = height;
+ st->codecpar->sample_rate= sample_rate;
+ st->codecpar->channels = channels;
+ st->codecpar->format = format;
+ st->priv_data = av_packet_alloc();
+ if (!st->priv_data)
+ return AVERROR(ENOMEM);
+
+ if (sample_rate)
+ avpriv_set_pts_info(st, 63, 1, sample_rate);
+ else
+ avpriv_set_pts_info(st, 63, fps.den, fps.num);
+ }
+ }
+
+ return 0;
+}
+
+static int moflex_read_header(AVFormatContext *s)
+{
+ int ret;
+
+ ret = moflex_read_sync(s);
+ if (ret < 0)
+ return ret;
+
+ s->ctx_flags |= AVFMTCTX_NOHEADER;
+ avio_seek(s->pb, 0, SEEK_SET);
+
+ return 0;
+}
+
+static int moflex_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ MOFLEXDemuxContext *m = s->priv_data;
+ AVIOContext *pb = s->pb;
+ BitReader *br = &m->br;
+ int ret;
+
+ while (!avio_feof(pb)) {
+ if (!m->in_block) {
+ m->pos = avio_tell(pb);
+
+ ret = moflex_read_sync(s);
+ if (ret < 0)
+ return ret;
+
+ m->flags = avio_r8(pb);
+ if (m->flags & 2)
+ avio_skip(pb, 2);
+ }
+
+ while ((avio_tell(pb) < m->pos + m->size) && !avio_feof(pb) && avio_r8(pb)) {
+ int stream_index, bits, pkt_size, endframe;
+ AVPacket *packet;
+
+ m->in_block = 1;
+
+ avio_seek(pb, -1, SEEK_CUR);
+ br->pos = br->last = 0;
+
+ bits = pop_length(br, pb);
+ if (bits < 0)
+ return bits;
+ stream_index = pop_int(br, pb, bits);
+ if (stream_index < 0)
+ return stream_index;
+ if (stream_index >= s->nb_streams)
+ return AVERROR_INVALIDDATA;
+
+ endframe = pop(br, pb);
+ if (endframe < 0)
+ return endframe;
+ if (endframe) {
+ bits = pop_length(br, pb);
+ if (bits < 0)
+ return bits;
+ pop_int(br, pb, bits);
+ pop(br, pb);
+ bits = pop_length(br, pb);
+ if (bits < 0)
+ return bits;
+ pop_int(br, pb, bits * 2 + 26);
+ }
+
+ pkt_size = pop_int(br, pb, 13) + 1;
+ packet = s->streams[stream_index]->priv_data;
+
+ ret = av_append_packet(pb, packet, pkt_size);
+ if (endframe) {
+ av_packet_move_ref(pkt, packet);
+ pkt->pos = m->pos;
+ pkt->stream_index = stream_index;
+ pkt->flags |= AV_PKT_FLAG_KEY;
+ return ret;
+ }
+ }
+
+ m->in_block = 0;
+
+ if (m->flags % 2 == 0)
+ avio_seek(pb, m->pos + m->size, SEEK_SET);
+ }
+
+ return AVERROR_EOF;
+}
+
+static int moflex_read_close(AVFormatContext *s)
+{
+ for (int i = 0; i < s->nb_streams; i++) {
+ AVPacket *packet = s->streams[i]->priv_data;
+
+ av_packet_free(&packet);
+ s->streams[i]->priv_data = 0;
+ }
+
+ return 0;
+}
+
+AVInputFormat ff_moflex_demuxer = {
+ .name = "moflex",
+ .long_name = NULL_IF_CONFIG_SMALL("MobiClip MOFLEX"),
+ .priv_data_size = sizeof(MOFLEXDemuxContext),
+ .read_probe = moflex_probe,
+ .read_header = moflex_read_header,
+ .read_packet = moflex_read_packet,
+ .read_close = moflex_read_close,
+ .extensions = "moflex",
+ .flags = AVFMT_GENERIC_INDEX,
+};
--
2.17.1
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