[FFmpeg-devel] [PATCH] Add AVIO_FLAG_DIRECT.
Reimar Döffinger
Reimar.Doeffinger at gmx.de
Wed Mar 28 22:26:35 CEST 2012
Allows avoiding the buffer when using avio read and write functions.
The test does not work: It works for testing reading, but for
writing avio_flags never gets set in the ffmpeg.c part of the change.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger at gmx.de>
---
ffmpeg.c | 2 +-
libavformat/avformat.h | 2 ++
libavformat/avio.h | 13 +++++++++++++
libavformat/aviobuf.c | 31 ++++++++++++++++++++++---------
libavformat/options_table.h | 2 ++
libavformat/utils.c | 2 +-
tests/fate/demux.mak | 3 +++
7 files changed, 44 insertions(+), 11 deletions(-)
diff --git a/ffmpeg.c b/ffmpeg.c
index d5e789e..1cba743 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -4542,7 +4542,7 @@ static void opt_output_file(void *optctx, const char *filename)
assert_file_overwrite(filename);
/* open the file */
- if ((err = avio_open2(&oc->pb, filename, AVIO_FLAG_WRITE,
+ if ((err = avio_open2(&oc->pb, filename, AVIO_FLAG_WRITE | oc->avio_flags,
&oc->interrupt_callback,
&output_files[nb_output_files - 1].opts)) < 0) {
print_error(filename, err);
diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index 7c307a7..5a11fdc 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -1083,6 +1083,8 @@ typedef struct AVFormatContext {
*/
#define RAW_PACKET_BUFFER_SIZE 2500000
int raw_packet_buffer_remaining_size;
+
+ int avio_flags;
} AVFormatContext;
typedef struct AVPacketList {
diff --git a/libavformat/avio.h b/libavformat/avio.h
index 95f9558..b4c975f 100644
--- a/libavformat/avio.h
+++ b/libavformat/avio.h
@@ -121,6 +121,12 @@ typedef struct {
* This field is internal to libavformat and access from outside is not allowed.
*/
int64_t maxsize;
+
+ /**
+ * avoi_read and avio_write should if possible be satisfied directly
+ * instead of going through a buffer.
+ */
+ int direct;
} AVIOContext;
/* unbuffered I/O */
@@ -320,6 +326,13 @@ int avio_get_str16be(AVIOContext *pb, int maxlen, char *buf, int buflen);
#define AVIO_FLAG_NONBLOCK 8
/**
+ * Use direct mode.
+ * avoi_read and avio_write should if possible be satisfied directly
+ * instead of going through a buffer.
+ */
+#define AVIO_FLAG_DIRECT 0x8000
+
+/**
* Create and initialize a AVIOContext for accessing the
* resource indicated by url.
* @note When the resource indicated by url has been opened in
diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c
index d1520ed..5e777fa 100644
--- a/libavformat/aviobuf.c
+++ b/libavformat/aviobuf.c
@@ -80,6 +80,7 @@ int ffio_init_context(AVIOContext *s,
s->buffer_size = buffer_size;
s->buf_ptr = buffer;
s->opaque = opaque;
+ s->direct = 0;
url_resetbuf(s, write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
s->write_packet = write_packet;
s->read_packet = read_packet;
@@ -117,20 +118,25 @@ AVIOContext *avio_alloc_context(
return s;
}
+static void writeout(AVIOContext *s, const uint8_t *data, int len)
+{
+ if (s->write_packet && !s->error){
+ int ret= s->write_packet(s->opaque, data, len);
+ if(ret < 0){
+ s->error = ret;
+ }
+ }
+ s->pos += len;
+}
+
static void flush_buffer(AVIOContext *s)
{
if (s->buf_ptr > s->buffer) {
- if (s->write_packet && !s->error){
- int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
- if(ret < 0){
- s->error = ret;
- }
- }
+ writeout(s, s->buffer, s->buf_ptr - s->buffer);
if(s->update_checksum){
s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
s->checksum_ptr= s->buffer;
}
- s->pos += s->buf_ptr - s->buffer;
}
s->buf_ptr = s->buffer;
}
@@ -158,6 +164,11 @@ void ffio_fill(AVIOContext *s, int b, int count)
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
{
+ if (s->direct) {
+ avio_flush(s);
+ writeout(s, buf, size);
+ return;
+ }
while (size > 0) {
int len = FFMIN(s->buf_end - s->buf_ptr, size);
memcpy(s->buf_ptr, buf, len);
@@ -199,13 +210,14 @@ int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
offset += offset1;
}
offset1 = offset - pos;
- if (!s->must_flush &&
+ if (!s->must_flush && !s->direct &&
offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
/* can do the seek inside the buffer */
s->buf_ptr = s->buffer + offset1;
} else if ((!s->seekable ||
offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
!s->write_flag && offset1 >= 0 &&
+ !s->direct &&
(whence != SEEK_END || force)) {
while(s->pos < offset && !s->eof_reached)
fill_buffer(s);
@@ -458,7 +470,7 @@ int avio_read(AVIOContext *s, unsigned char *buf, int size)
if (len > size)
len = size;
if (len == 0) {
- if(size > s->buffer_size && !s->update_checksum){
+ if((s->direct || size > s->buffer_size) && !s->update_checksum){
if(s->read_packet)
len = s->read_packet(s->opaque, buf, size);
if (len <= 0) {
@@ -670,6 +682,7 @@ int ffio_fdopen(AVIOContext **s, URLContext *h)
av_free(buffer);
return AVERROR(ENOMEM);
}
+ (*s)->direct = h->flags & AVIO_FLAG_DIRECT;
(*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
(*s)->max_packet_size = max_packet_size;
if(h->prot) {
diff --git a/libavformat/options_table.h b/libavformat/options_table.h
index 0313839..8d57c27 100644
--- a/libavformat/options_table.h
+++ b/libavformat/options_table.h
@@ -28,6 +28,8 @@
#define D AV_OPT_FLAG_DECODING_PARAM
static const AVOption options[]={
+{"avioflags", NULL, OFFSET(avio_flags), AV_OPT_TYPE_FLAGS, {.dbl = DEFAULT }, INT_MIN, INT_MAX, D|E, "avioflags"},
+{"direct", "reduce buffering", 0, AV_OPT_TYPE_CONST, {.dbl = AVIO_FLAG_DIRECT }, INT_MIN, INT_MAX, D|E, "avioflags"},
{"probesize", "set probing size", OFFSET(probesize), AV_OPT_TYPE_INT, {.dbl = 5000000 }, 32, INT_MAX, D},
{"packetsize", "set packet size", OFFSET(packet_size), AV_OPT_TYPE_INT, {.dbl = DEFAULT }, 0, INT_MAX, E},
{"fflags", NULL, OFFSET(flags), AV_OPT_TYPE_FLAGS, {.dbl = DEFAULT }, INT_MIN, INT_MAX, D|E, "fflags"},
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 0f8b940..3d0d989 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -543,7 +543,7 @@ static int init_input(AVFormatContext *s, const char *filename, AVDictionary **o
(!s->iformat && (s->iformat = av_probe_input_format(&pd, 0))))
return 0;
- if ((ret = avio_open2(&s->pb, filename, AVIO_FLAG_READ,
+ if ((ret = avio_open2(&s->pb, filename, AVIO_FLAG_READ | s->avio_flags,
&s->interrupt_callback, options)) < 0)
return ret;
if (s->iformat)
diff --git a/tests/fate/demux.mak b/tests/fate/demux.mak
index 5e5c8e1..5d3ad44 100644
--- a/tests/fate/demux.mak
+++ b/tests/fate/demux.mak
@@ -1,3 +1,6 @@
+FATE_DEMUX += fate-avio-direct
+fate-avio-direct: CMD = framecrc -avioflags direct -i $(SAMPLES)/fraps/fraps-v5-bouncing-balls-partial.avi -avioflags direct
+
FATE_DEMUX += fate-adts-demux
fate-adts-demux: CMD = crc -i $(SAMPLES)/aac/ct_faac-adts.aac -acodec copy
--
1.7.9.1
More information about the ffmpeg-devel
mailing list