From edea15657981ac85baa058f6cdb5588171349b83 Mon Sep 17 00:00:00 2001 From: Timotej Lazar Date: Wed, 17 Jun 2020 21:45:39 +0200 Subject: avformat/smacker: Support seeking to first frame MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add .read_seek function to the smacker demuxer for the special case of seeking to ts=0. This is useful because smacker – like bink, with a similar implementation – was mostly used to encode clips in video games, where random seeks are rare but looping media are common. Signed-off-by: Timotej Lazar --- libavformat/smacker.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/libavformat/smacker.c b/libavformat/smacker.c index 0ca5a87b8f..5507e7c169 100644 --- a/libavformat/smacker.c +++ b/libavformat/smacker.c @@ -349,6 +349,31 @@ next_frame: return ret; } +static int smacker_read_seek(AVFormatContext *s, int stream_index, + int64_t timestamp, int flags) +{ + SmackerContext *smk = s->priv_data; + int64_t ret; + + /* only rewinding to start is supported */ + if (timestamp != 0) { + av_log(s, AV_LOG_ERROR, + "Random seeks are not supported (can only seek to start).\n"); + return AVERROR(EINVAL); + } + + if ((ret = avio_seek(s->pb, s->internal->data_offset, SEEK_SET)) < 0) + return ret; + + smk->cur_frame = 0; + smk->next_audio_index = 0; + smk->new_palette = 0; + memset(smk->pal, 0, sizeof(smk->pal)); + memset(smk->aud_pts, 0, sizeof(smk->aud_pts)); + + return 0; +} + AVInputFormat ff_smacker_demuxer = { .name = "smk", .long_name = NULL_IF_CONFIG_SMALL("Smacker"), @@ -356,4 +381,5 @@ AVInputFormat ff_smacker_demuxer = { .read_probe = smacker_probe, .read_header = smacker_read_header, .read_packet = smacker_read_packet, + .read_seek = smacker_read_seek, }; -- cgit v1.2.3