From 01f1f017d831cf14617aaaeafcec3ae3a81efce7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Peter=20Gro=C3=9Fe?= Date: Sun, 29 Jan 2017 15:26:31 +0100 Subject: [PATCH] dashenc: use avio_dynbuf instead of packet_write callback MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The dash_write function drops data, if no IOContext is initialized. Since the mp4 muxer is used in "frag_custom" mode, data is only written when calling av_write_frame(NULL) explicitly and thus there will be no data loss. To add support for webm as subordinate muxer, which doesn't have such a mode, a dynamic buffer is required to provide an always initialized IOContext. Signed-off-by: Peter Große Signed-off-by: Martin Storsjö --- libavformat/dashenc.c | 61 +++++++++++++++++++++++++------------------ 1 file changed, 36 insertions(+), 25 deletions(-) diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c index 8b70278b39..78ebc0628a 100644 --- a/libavformat/dashenc.c +++ b/libavformat/dashenc.c @@ -67,11 +67,10 @@ typedef struct AdaptationSet { typedef struct OutputStream { AVFormatContext *ctx; int ctx_inited, as_idx; - uint8_t iobuf[32768]; AVIOContext *out; int packets_written; char initfile[1024]; - int64_t init_start_pos; + int64_t init_start_pos, pos; int init_range_length; int nb_segments, segments_size, segment_index; Segment **segments; @@ -107,14 +106,6 @@ typedef struct DASHContext { const char *utc_timing_url; } DASHContext; -static int dash_write(void *opaque, uint8_t *buf, int buf_size) -{ - OutputStream *os = opaque; - if (os->out) - avio_write(os->out, buf, buf_size); - return buf_size; -} - // RFC 6381 static void set_codec_str(AVFormatContext *s, AVCodecParameters *par, char *str, int size) @@ -181,6 +172,28 @@ static void set_codec_str(AVFormatContext *s, AVCodecParameters *par, } } +static int flush_dynbuf(OutputStream *os, int *range_length) +{ + uint8_t *buffer; + + if (!os->ctx->pb) { + return AVERROR(EINVAL); + } + + // flush + av_write_frame(os->ctx, NULL); + avio_flush(os->ctx->pb); + + // write out to file + *range_length = avio_close_dyn_buf(os->ctx->pb, &buffer); + os->ctx->pb = NULL; + avio_write(os->out, buffer, *range_length); + av_free(buffer); + + // re-open buffer + return avio_open_dyn_buf(&os->ctx->pb); +} + static void dash_free(AVFormatContext *s) { DASHContext *c = s->priv_data; @@ -200,7 +213,7 @@ static void dash_free(AVFormatContext *s) if (os->ctx && os->ctx_inited) av_write_trailer(os->ctx); if (os->ctx && os->ctx->pb) - av_free(os->ctx->pb); + ffio_free_dyn_buf(&os->ctx->pb); ff_format_io_close(s, &os->out); if (os->ctx) avformat_free_context(os->ctx); @@ -806,11 +819,8 @@ static int dash_write_header(AVFormatContext *s) st->time_base = s->streams[i]->time_base; ctx->avoid_negative_ts = s->avoid_negative_ts; - ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf), AVIO_FLAG_WRITE, os, NULL, dash_write, NULL); - if (!ctx->pb) { - ret = AVERROR(ENOMEM); + if ((ret = avio_open_dyn_buf(&ctx->pb)) < 0) goto fail; - } if (c->single_file) { if (c->single_file_name) @@ -966,7 +976,6 @@ static int dash_flush(AVFormatContext *s, int final, int stream) for (i = 0; i < s->nb_streams; i++) { OutputStream *os = &c->streams[i]; char filename[1024] = "", full_path[1024], temp_path[1024]; - int64_t start_pos; int range_length, index_length = 0; if (!os->packets_written) @@ -985,14 +994,14 @@ static int dash_flush(AVFormatContext *s, int final, int stream) } if (!os->init_range_length) { - av_write_frame(os->ctx, NULL); - os->init_range_length = avio_tell(os->ctx->pb); + ret = flush_dynbuf(os, &range_length); + if (ret < 0) + break; + os->pos = os->init_range_length = range_length; if (!c->single_file) ff_format_io_close(s, &os->out); } - start_pos = avio_tell(os->ctx->pb); - if (!c->single_file) { dash_fill_tmpl_params(filename, sizeof(filename), c->media_seg_name, i, os->segment_index, os->bit_rate, os->start_pts); snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, filename); @@ -1005,13 +1014,13 @@ static int dash_flush(AVFormatContext *s, int final, int stream) snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, os->initfile); } - av_write_frame(os->ctx, NULL); - avio_flush(os->ctx->pb); + ret = flush_dynbuf(os, &range_length); + if (ret < 0) + break; os->packets_written = 0; - range_length = avio_tell(os->ctx->pb) - start_pos; if (c->single_file) { - find_index_range(s, full_path, start_pos, &index_length); + find_index_range(s, full_path, os->pos, &index_length); } else { ff_format_io_close(s, &os->out); ret = ff_rename(temp_path, full_path); @@ -1028,8 +1037,10 @@ static int dash_flush(AVFormatContext *s, int final, int stream) " bandwidth=\"%d\"", os->bit_rate); } } - add_segment(os, filename, os->start_pts, os->max_pts - os->start_pts, start_pos, range_length, index_length); + add_segment(os, filename, os->start_pts, os->max_pts - os->start_pts, os->pos, range_length, index_length); av_log(s, AV_LOG_VERBOSE, "Representation %d media segment %d written to: %s\n", i, os->segment_index, full_path); + + os->pos += range_length; } if (c->window_size || (final && c->remove_at_exit)) {