[FFmpeg-devel] [PATCH v1] avformat/flvenc: add add_keyframe_index option
Michael Niedermayer
michael at niedermayer.cc
Fri Nov 4 14:44:50 EET 2016
On Fri, Nov 04, 2016 at 11:24:06AM +0800, Steven Liu wrote:
> Add keyframe index metadata
> Used to facilitate seeking; particularly for HTTP pseudo streaming.
>
> Reviewed-by: Lou Logan <lou at lrcd.com>
> Signed-off-by: Steven Liu <liuqi at gosun.com>
> ---
> doc/muxers.texi | 3 +
> libavformat/flvenc.c | 331 ++++++++++++++++++++++++++++++++++++++++++++++++--
> 2 files changed, 324 insertions(+), 10 deletions(-)
>
> diff --git a/doc/muxers.texi b/doc/muxers.texi
> index 488ed43..806182a 100644
> --- a/doc/muxers.texi
> +++ b/doc/muxers.texi
> @@ -147,6 +147,9 @@ Place AAC sequence header based on audio stream data.
>
> @item no_sequence_end
> Disable sequence end tag.
> +
> + at item add_keyframe_index
> +Used to facilitate seeking; particularly for HTTP pseudo streaming.
> @end table
> @end table
>
> diff --git a/libavformat/flvenc.c b/libavformat/flvenc.c
> index e50f8e4..ee06a92 100644
> --- a/libavformat/flvenc.c
> +++ b/libavformat/flvenc.c
> @@ -24,6 +24,8 @@
> #include "libavutil/intfloat.h"
> #include "libavutil/avassert.h"
> #include "libavutil/mathematics.h"
> +#include "avio_internal.h"
> +#include "avio.h"
> #include "avc.h"
> #include "avformat.h"
> #include "flv.h"
> @@ -64,8 +66,15 @@ static const AVCodecTag flv_audio_codec_ids[] = {
> typedef enum {
> FLV_AAC_SEQ_HEADER_DETECT = (1 << 0),
> FLV_NO_SEQUENCE_END = (1 << 1),
> + FLV_ADD_KEYFRAME_INDEX = (1 << 2),
> } FLVFlags;
>
> +typedef struct FLVFileposition {
> + int64_t keyframe_position;
> + double keyframe_timestamp;
> + struct FLVFileposition *next;
> +} FLVFileposition;
> +
> typedef struct FLVContext {
> AVClass *av_class;
> int reserved;
> @@ -74,6 +83,33 @@ typedef struct FLVContext {
> int64_t duration;
> int64_t delay; ///< first dts delay (needed for AVC & Speex)
>
> + int64_t datastart_offset;
> + int64_t datasize_offset;
> + int64_t datasize;
> + int64_t videosize_offset;
> + int64_t videosize;
> + int64_t audiosize_offset;
> + int64_t audiosize;
> +
> + int64_t metadata_size_pos;
> + int64_t metadata_totalsize_pos;
> + int64_t metadata_totalsize;
> + int64_t keyframe_index_size;
> +
> + int64_t lasttimestamp_offset;
> + double lasttimestamp;
> + int64_t lastkeyframetimestamp_offset;
> + double lastkeyframetimestamp;
> + int64_t lastkeyframelocation_offset;
> + int64_t lastkeyframelocation;
> +
> + int acurframeindex;
> + int64_t keyframes_info_offset;
> +
> + int64_t filepositions_count;
> + FLVFileposition *filepositions;
> + FLVFileposition *head_filepositions;
> +
> AVCodecParameters *audio_par;
> AVCodecParameters *video_par;
> double framerate;
> @@ -202,6 +238,17 @@ static void put_amf_double(AVIOContext *pb, double d)
> avio_wb64(pb, av_double2int(d));
> }
>
> +static void put_amf_byte(AVIOContext *pb, unsigned char abyte)
> +{
> + avio_w8(pb, abyte);
> +}
> +
> +static void put_amf_dword_array(AVIOContext *pb, uint32_t dw)
> +{
> + avio_w8(pb, AMF_DATA_TYPE_ARRAY);
> + avio_wb32(pb, dw);
> +}
> +
> static void put_amf_bool(AVIOContext *pb, int b)
> {
> avio_w8(pb, AMF_DATA_TYPE_BOOL);
> @@ -213,12 +260,12 @@ static void write_metadata(AVFormatContext *s, unsigned int ts)
> AVIOContext *pb = s->pb;
> FLVContext *flv = s->priv_data;
> int metadata_count = 0;
> - int64_t metadata_size_pos, data_size, metadata_count_pos;
> + int64_t metadata_count_pos;
> AVDictionaryEntry *tag = NULL;
>
> /* write meta_tag */
> - avio_w8(pb, 18); // tag type META
> - metadata_size_pos = avio_tell(pb);
> + avio_w8(pb, FLV_TAG_TYPE_META); // tag type META
> + flv->metadata_size_pos = avio_tell(pb);
> avio_wb24(pb, 0); // size of data part (sum of all parts below)
> avio_wb24(pb, ts); // timestamp
> avio_wb32(pb, 0); // reserved
> @@ -327,19 +374,87 @@ static void write_metadata(AVFormatContext *s, unsigned int ts)
> put_amf_double(pb, 0); // delayed write
> }
>
> + if (flv->flags & FLV_ADD_KEYFRAME_INDEX) {
> + flv->acurframeindex = 0;
> + flv->keyframe_index_size = 0;
> +
> + put_amf_string(pb, "hasVideo");
> + put_amf_bool(pb, !!flv->video_par);
> + metadata_count++;
> +
> + put_amf_string(pb, "hasKeyframes");
> + put_amf_bool(pb, 1);
> + metadata_count++;
> +
> + put_amf_string(pb, "hasAudio");
> + put_amf_bool(pb, !!flv->audio_par);
> + metadata_count++;
> +
> + put_amf_string(pb, "hasMetadata");
> + put_amf_bool(pb, 1);
> + metadata_count++;
> +
> + put_amf_string(pb, "canSeekToEnd");
> + put_amf_bool(pb, 1);
> + metadata_count++;
> +
> + put_amf_string(pb, "datasize");
> + flv->datasize_offset = avio_tell(pb);
> + flv->datasize = 0;
> + put_amf_double(pb, flv->datasize);
> + metadata_count++;
> +
> + put_amf_string(pb, "videosize");
> + flv->videosize_offset = avio_tell(pb);
> + flv->videosize = 0;
> + put_amf_double(pb, flv->videosize);
> + metadata_count++;
> +
> + put_amf_string(pb, "audiosize");
> + flv->audiosize_offset = avio_tell(pb);
> + flv->audiosize = 0;
> + put_amf_double(pb, flv->audiosize);
> + metadata_count++;
> +
> + put_amf_string(pb, "lasttimestamp");
> + flv->lasttimestamp_offset = avio_tell(pb);
> + flv->lasttimestamp = 0;
> + put_amf_double(pb, 0);
> + metadata_count++;
> +
> + put_amf_string(pb, "lastkeyframetimestamp");
> + flv->lastkeyframetimestamp_offset = avio_tell(pb);
> + flv->lastkeyframetimestamp = 0;
> + put_amf_double(pb, 0);
> + metadata_count++;
> +
> + put_amf_string(pb, "lastkeyframelocation");
> + flv->lastkeyframelocation_offset = avio_tell(pb);
> + flv->lastkeyframelocation = 0;
> + put_amf_double(pb, 0);
> + metadata_count++;
> +
> + put_amf_string(pb, "keyframes");
> + put_amf_byte(pb, AMF_DATA_TYPE_OBJECT);
> + metadata_count++;
> +
> + flv->keyframes_info_offset = avio_tell(pb);
> + }
> +
> put_amf_string(pb, "");
> avio_w8(pb, AMF_END_OF_OBJECT);
>
> /* write total size of tag */
> - data_size = avio_tell(pb) - metadata_size_pos - 10;
> + flv->metadata_totalsize = avio_tell(pb) - flv->metadata_size_pos - 10;
>
> avio_seek(pb, metadata_count_pos, SEEK_SET);
> avio_wb32(pb, metadata_count);
>
> - avio_seek(pb, metadata_size_pos, SEEK_SET);
> - avio_wb24(pb, data_size);
> - avio_skip(pb, data_size + 10 - 3);
> - avio_wb32(pb, data_size + 11);
> + avio_seek(pb, flv->metadata_size_pos, SEEK_SET);
> + avio_wb24(pb, flv->metadata_totalsize);
> + avio_skip(pb, flv->metadata_totalsize + 10 - 3);
> + flv->metadata_totalsize_pos = avio_tell(pb);
> + avio_wb32(pb, flv->metadata_totalsize + 11);
> }
>
> static int unsupported_codec(AVFormatContext *s,
> @@ -416,6 +531,111 @@ static void flv_write_codec_header(AVFormatContext* s, AVCodecParameters* par) {
> }
> }
>
> +static int flv_append_keyframe_info(AVFormatContext *s, FLVContext *flv, double ts, int64_t pos)
> +{
> + FLVFileposition *position = av_malloc(sizeof(FLVFileposition));
> +
> + if (!position) {
> + av_log(s, AV_LOG_WARNING, "no mem for add keyframe index!\n");
> + return AVERROR(ENOMEM);
> + }
> +
> + position->keyframe_timestamp = ts;
> + position->keyframe_position = pos;
> +
> + if (flv->filepositions_count) {
> + flv->filepositions = position;
> + flv->head_filepositions = flv->filepositions;
> + position->next = NULL;
> + } else {
> + flv->filepositions->next = position;
> + position->next = NULL;
> + flv->filepositions = flv->filepositions->next;
> + }
> +
> + flv->filepositions_count++;
> +
> + return 0;
> +}
an array should be more space efficient than a linked list
maybe i miss something but
cant you simply use av_add_index_entry() ?
> +
> +static int shift_data(AVFormatContext *s)
> +{
> + int ret = 0;
> + int n = 0;
> + int metadata_size = 0;
> + FLVContext *flv = s->priv_data;
> + int64_t pos, pos_end = avio_tell(s->pb);
> + uint8_t *buf, *read_buf[2];
> + int read_buf_id = 0;
> + int read_size[2];
> + AVIOContext *read_pb;
> +
> + metadata_size = flv->filepositions_count * 9 * 2 + 10; /* filepositions and times value */
The multiplications need checks for overflow i think or the type
must be larger (int64) if filepositions_count is 32 or oterwise
limited
> + metadata_size += 2 + 13; /* filepositions String */
> + metadata_size += 2 + 5; /* times String */
> + metadata_size += 3; /* Object end */
> +
> + flv->keyframe_index_size = metadata_size;
> +
> + if (metadata_size < 0)
> + return metadata_size;
> +
> + buf = av_malloc(metadata_size * 2);
av_malloc_array()
[...]
--
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
While the State exists there can be no freedom; when there is freedom there
will be no State. -- Vladimir Lenin
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