[FFmpeg-devel] [PATCH 1/2] avformat/dv: Avoid alloction of DVDemuxContext
Andreas Rheinhardt
andreas.rheinhardt at gmail.com
Sun Aug 2 14:47:30 EEST 2020
This commit avoids allocating a DVDemuxContext when demuxing raw DV by
making it part of the demuxer's context. This also allows to remove
dv_read_close().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
---
libavformat/dv.c | 73 +++++++++++++++++++++---------------------------
1 file changed, 32 insertions(+), 41 deletions(-)
diff --git a/libavformat/dv.c b/libavformat/dv.c
index e99422d4b5..9179e6cec6 100644
--- a/libavformat/dv.c
+++ b/libavformat/dv.c
@@ -321,6 +321,21 @@ static int dv_extract_timecode(DVDemuxContext* c, const uint8_t* frame, char *tc
/* The following 3 functions constitute our interface to the world */
+static int dv_init_demux(AVFormatContext *s, DVDemuxContext *c)
+{
+ c->vst = avformat_new_stream(s, NULL);
+ if (!c->vst)
+ return AVERROR(ENOMEM);
+
+ c->fctx = s;
+ c->vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+ c->vst->codecpar->codec_id = AV_CODEC_ID_DVVIDEO;
+ c->vst->codecpar->bit_rate = 25000000;
+ c->vst->start_time = 0;
+
+ return 0;
+}
+
DVDemuxContext *avpriv_dv_init_demux(AVFormatContext *s)
{
DVDemuxContext *c;
@@ -329,18 +344,11 @@ DVDemuxContext *avpriv_dv_init_demux(AVFormatContext *s)
if (!c)
return NULL;
- c->vst = avformat_new_stream(s, NULL);
- if (!c->vst) {
+ if (dv_init_demux(s, c)) {
av_free(c);
return NULL;
}
- c->fctx = s;
- c->vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
- c->vst->codecpar->codec_id = AV_CODEC_ID_DVVIDEO;
- c->vst->codecpar->bit_rate = 25000000;
- c->vst->start_time = 0;
-
return c;
}
@@ -452,7 +460,7 @@ void ff_dv_offset_reset(DVDemuxContext *c, int64_t frame_offset)
************************************************************/
typedef struct RawDVContext {
- DVDemuxContext *dv_demux;
+ DVDemuxContext dv_demux;
uint8_t buf[DV_MAX_FRAME_SIZE];
} RawDVContext;
@@ -479,7 +487,7 @@ static int dv_read_timecode(AVFormatContext *s) {
goto finish;
}
- ret = dv_extract_timecode(c->dv_demux, partial_frame, timecode);
+ ret = dv_extract_timecode(&c->dv_demux, partial_frame, timecode);
if (ret)
av_dict_set(&s->metadata, "timecode", timecode, 0);
else
@@ -497,16 +505,14 @@ static int dv_read_header(AVFormatContext *s)
RawDVContext *c = s->priv_data;
int ret;
- c->dv_demux = avpriv_dv_init_demux(s);
- if (!c->dv_demux)
- return AVERROR(ENOMEM);
+ if ((ret = dv_init_demux(s, &c->dv_demux)) < 0)
+ return ret;
state = avio_rb32(s->pb);
while ((state & 0xffffff7f) != 0x1f07003f) {
if (avio_feof(s->pb)) {
av_log(s, AV_LOG_ERROR, "Cannot find DV header.\n");
- ret = AVERROR_INVALIDDATA;
- goto fail;
+ return AVERROR_INVALIDDATA;
}
if (state == 0x003f0700 || state == 0xff3f0700)
marker_pos = avio_tell(s->pb);
@@ -521,33 +527,26 @@ static int dv_read_header(AVFormatContext *s)
if (avio_read(s->pb, c->buf + 4, DV_PROFILE_BYTES - 4) != DV_PROFILE_BYTES - 4 ||
avio_seek(s->pb, -DV_PROFILE_BYTES, SEEK_CUR) < 0) {
- ret = AVERROR(EIO);
- goto fail;
+ return AVERROR(EIO);
}
- c->dv_demux->sys = av_dv_frame_profile(c->dv_demux->sys,
+ c->dv_demux.sys = av_dv_frame_profile(c->dv_demux.sys,
c->buf,
DV_PROFILE_BYTES);
- if (!c->dv_demux->sys) {
+ if (!c->dv_demux.sys) {
av_log(s, AV_LOG_ERROR,
"Can't determine profile of DV input stream.\n");
- ret = AVERROR_INVALIDDATA;
- goto fail;
+ return AVERROR_INVALIDDATA;
}
- s->bit_rate = av_rescale_q(c->dv_demux->sys->frame_size,
+ s->bit_rate = av_rescale_q(c->dv_demux.sys->frame_size,
(AVRational) { 8, 1 },
- c->dv_demux->sys->time_base);
+ c->dv_demux.sys->time_base);
if (s->pb->seekable & AVIO_SEEKABLE_NORMAL)
dv_read_timecode(s);
return 0;
-
-fail:
- av_freep(&c->dv_demux);
-
- return ret;
}
static int dv_read_packet(AVFormatContext *s, AVPacket *pkt)
@@ -555,14 +554,14 @@ static int dv_read_packet(AVFormatContext *s, AVPacket *pkt)
int size;
RawDVContext *c = s->priv_data;
- size = avpriv_dv_get_packet(c->dv_demux, pkt);
+ size = avpriv_dv_get_packet(&c->dv_demux, pkt);
if (size < 0) {
int ret;
int64_t pos = avio_tell(s->pb);
- if (!c->dv_demux->sys)
+ if (!c->dv_demux.sys)
return AVERROR(EIO);
- size = c->dv_demux->sys->frame_size;
+ size = c->dv_demux.sys->frame_size;
ret = avio_read(s->pb, c->buf, size);
if (ret < 0) {
return ret;
@@ -570,7 +569,7 @@ static int dv_read_packet(AVFormatContext *s, AVPacket *pkt)
return AVERROR(EIO);
}
- size = avpriv_dv_produce_packet(c->dv_demux, pkt, c->buf, size, pos);
+ size = avpriv_dv_produce_packet(&c->dv_demux, pkt, c->buf, size, pos);
}
return size;
@@ -580,7 +579,7 @@ static int dv_read_seek(AVFormatContext *s, int stream_index,
int64_t timestamp, int flags)
{
RawDVContext *r = s->priv_data;
- DVDemuxContext *c = r->dv_demux;
+ DVDemuxContext *c = &r->dv_demux;
int64_t offset = dv_frame_offset(s, c, timestamp, flags);
if (avio_seek(s->pb, offset, SEEK_SET) < 0)
@@ -590,13 +589,6 @@ static int dv_read_seek(AVFormatContext *s, int stream_index,
return 0;
}
-static int dv_read_close(AVFormatContext *s)
-{
- RawDVContext *c = s->priv_data;
- av_freep(&c->dv_demux);
- return 0;
-}
-
static int dv_probe(const AVProbeData *p)
{
unsigned marker_pos = 0;
@@ -646,7 +638,6 @@ AVInputFormat ff_dv_demuxer = {
.read_probe = dv_probe,
.read_header = dv_read_header,
.read_packet = dv_read_packet,
- .read_close = dv_read_close,
.read_seek = dv_read_seek,
.extensions = "dv,dif",
};
--
2.20.1
More information about the ffmpeg-devel
mailing list