Please see updated v2: https://patchwork.ffmpeg.org/project/ffmpeg/patch/[email protected]/
I've addressed all comments. Thank you. > On 9. Nov 2025, at 02:38, Vladimir Sobolev <[email protected]> wrote: > >> From 31d73c6774c1ea6d621db57f26439e297cc23c3d Mon Sep 17 00:00:00 2001 > From: Vladimir Sobolev <[email protected]> > Date: Sun, 9 Nov 2025 02:28:13 +0200 > Subject: [PATCH] avformat/mpjpegdec: add support for X-Timestamp and > X-Framerate headers > > Add support for parsing X-Timestamp and X-Framerate headers from > HTTP multipart MJPEG streams. These headers allow servers to provide > accurate timestamps and framerate information for each frame. > > Changes: > - Parse X-Timestamp header (in seconds) and set packet PTS/DTS > - Parse X-Framerate/X-FrameRate header and update stream framerate > - Maintain backward compatibility (defaults to 25 fps if not provided) > - Add debug logging for parsed header values > > This enables proper timestamp handling for MJPEG streams that provide > timing information in HTTP headers, improving synchronization accuracy. > --- > libavformat/mpjpegdec.c | 69 ++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 65 insertions(+), 4 deletions(-) > > diff --git a/libavformat/mpjpegdec.c b/libavformat/mpjpegdec.c > index 125b17585e..c90d7a2ad4 100644 > --- a/libavformat/mpjpegdec.c > +++ b/libavformat/mpjpegdec.c > @@ -22,6 +22,9 @@ > #include "libavutil/avstring.h" > #include "libavutil/mem.h" > #include "libavutil/opt.h" > +#include "libavutil/parseutils.h" > +#include "libavutil/eval.h" > +#include "libavutil/intfloat.h" > > #include "avformat.h" > #include "demux.h" > @@ -34,6 +37,11 @@ typedef struct MPJPEGDemuxContext { > char *searchstr; > int searchstr_len; > int strict_mime_boundary; > + AVRational framerate; /* framerate from X-Framerate header */ > + int64_t timestamp; /* timestamp from X-Timestamp header */ > + int has_timestamp; /* flag indicating if timestamp was set */ > + int framerate_set; /* flag indicating if framerate was set in > header */ > + int framerate_applied; /* flag indicating if framerate was > applied to stream */ > } MPJPEGDemuxContext; > > static void trim_right(char *p) > @@ -97,7 +105,8 @@ static int split_tag_value(char **tag, char **value, char > *line) > static int parse_multipart_header(AVIOContext *pb, > int* size, > const char* expected_boundary, > - void *log_ctx); > + void *log_ctx, > + MPJPEGDemuxContext *mpjpeg); > > static int mpjpeg_read_close(AVFormatContext *s) > { > @@ -118,7 +127,7 @@ static int mpjpeg_read_probe(const AVProbeData *p) > > ffio_init_read_context(&pb, p->buf, p->buf_size); > > - ret = (parse_multipart_header(&pb.pub, &size, "--", NULL) >= 0) ? > AVPROBE_SCORE_MAX : 0; > + ret = (parse_multipart_header(&pb.pub, &size, "--", NULL, NULL) >= 0) ? > AVPROBE_SCORE_MAX : 0; > > return ret; > } > @@ -146,6 +155,12 @@ static int mpjpeg_read_header(AVFormatContext *s) > st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; > st->codecpar->codec_id = AV_CODEC_ID_MJPEG; > > + /* Default framerate is 25 fps, will be updated from headers if > available */ > + MPJPEGDemuxContext *mpjpeg = s->priv_data; > + mpjpeg->framerate = (AVRational){25, 1}; > + mpjpeg->framerate_set = 0; > + mpjpeg->framerate_applied = 0; > + mpjpeg->has_timestamp = 0; > avpriv_set_pts_info(st, 60, 1, 25); > > avio_seek(s->pb, pos, SEEK_SET); > @@ -167,7 +182,8 @@ static int parse_content_length(const char *value) > static int parse_multipart_header(AVIOContext *pb, > int* size, > const char* expected_boundary, > - void *log_ctx) > + void *log_ctx, > + MPJPEGDemuxContext *mpjpeg) > { > char line[128]; > int found_content_type = 0; > @@ -235,6 +251,33 @@ static int parse_multipart_header(AVIOContext *pb, > av_log(log_ctx, AV_LOG_WARNING, > "Invalid Content-Length value : %s\n", > value); > + } else if (mpjpeg && !av_strcasecmp(tag, "X-Timestamp")) { > + double ts = av_strtod(value, NULL); > + if (!isnan(ts) && isfinite(ts)) { > + /* X-Timestamp is in seconds, convert to AV_TIME_BASE */ > + mpjpeg->timestamp = (int64_t)(ts * AV_TIME_BASE); > + mpjpeg->has_timestamp = 1; > + if (log_ctx) > + av_log(log_ctx, AV_LOG_DEBUG, > + "Parsed X-Timestamp: %s -> %"PRId64" (%.6f > seconds)\n", > + value, mpjpeg->timestamp, ts); > + } else if (log_ctx) { > + av_log(log_ctx, AV_LOG_WARNING, > + "Invalid X-Timestamp value : %s\n", value); > + } > + } else if (mpjpeg && (!av_strcasecmp(tag, "X-Framerate") || > !av_strcasecmp(tag, "X-FrameRate"))) { > + AVRational fps = {0}; > + if (av_parse_video_rate(&fps, value) >= 0 && fps.num > 0 && > fps.den > 0) { > + mpjpeg->framerate = fps; > + mpjpeg->framerate_set = 1; > + if (log_ctx) > + av_log(log_ctx, AV_LOG_DEBUG, > + "Parsed X-Framerate: %s -> %d/%d fps\n", > + value, fps.num, fps.den); > + } else if (log_ctx) { > + av_log(log_ctx, AV_LOG_WARNING, > + "Invalid X-Framerate value : %s\n", value); > + } > } > } > > @@ -311,10 +354,21 @@ static int mpjpeg_read_packet(AVFormatContext *s, > AVPacket *pkt) > mpjpeg->searchstr_len = strlen(mpjpeg->searchstr); > } > > - ret = parse_multipart_header(s->pb, &size, mpjpeg->boundary, s); > + /* Reset timestamp flag for each packet */ > + mpjpeg->has_timestamp = 0; > + > + ret = parse_multipart_header(s->pb, &size, mpjpeg->boundary, s, mpjpeg); > if (ret < 0) > return ret; > > + /* Update framerate if it was set in header and hasn't been applied yet > */ > + if (mpjpeg->framerate_set && !mpjpeg->framerate_applied && s->nb_streams > > 0) { > + AVStream *st = s->streams[0]; > + st->avg_frame_rate = mpjpeg->framerate; > + avpriv_set_pts_info(st, 60, mpjpeg->framerate.den, > mpjpeg->framerate.num); > + mpjpeg->framerate_applied = 1; > + } > + > if (size > 0) { > /* size has been provided to us in MIME header */ > ret = av_get_packet(s->pb, pkt, size); > @@ -353,6 +407,13 @@ static int mpjpeg_read_packet(AVFormatContext *s, > AVPacket *pkt) > } > } > > + /* Set timestamp from X-Timestamp header if available */ > + if (ret >= 0 && mpjpeg->has_timestamp && s->nb_streams > 0) { > + AVStream *st = s->streams[0]; > + pkt->pts = av_rescale_q(mpjpeg->timestamp, AV_TIME_BASE_Q, > st->time_base); > + pkt->dts = pkt->pts; > + } > + > return ret; > } > _______________________________________________ ffmpeg-devel mailing list -- [email protected] To unsubscribe send an email to [email protected]
