From 3045ac286538641076ce4547cda677c3b159877f Mon Sep 17 00:00:00 2001
From: Lynne <dev@lynne.ee>
Date: Mon, 30 Oct 2023 05:38:17 +0100
Subject: [PATCH 1/2] decode: add ff_decode_skip_samples function
This is a convenience function, which is required to be called by decoders
needing to skip samples every time.
It automatically creates and increments side data.
This function is a simplified version of an earlier patch. It is only
able to add additional delay, rather than insert or override any.
---
libavcodec/decode.c | 17 +++++++++++++++++
libavcodec/decode.h | 8 ++++++++
2 files changed, 25 insertions(+)
@@ -299,6 +299,23 @@ static int64_t guess_correct_pts(AVCodecContext *ctx,
return pts;
}
+int ff_decode_skip_samples(AVCodecContext *avctx, AVFrame *frame, uint32_t skip)
+{
+ uint32_t val = 0;
+ AVFrameSideData *side = av_frame_get_side_data(frame, AV_FRAME_DATA_SKIP_SAMPLES);
+ if (!side) {
+ side = av_frame_new_side_data(frame, AV_FRAME_DATA_SKIP_SAMPLES, 10);
+ if (!side)
+ return AVERROR(ENOMEM);
+ }
+
+ val += AV_RL32(side->data);
+ val += skip;
+ AV_WL32(side->data, val);
+
+ return 0;
+}
+
static int discard_samples(AVCodecContext *avctx, AVFrame *frame, int64_t *discarded_samples)
{
AVCodecInternal *avci = avctx->internal;
@@ -155,4 +155,12 @@ int ff_hwaccel_frame_priv_alloc(AVCodecContext *avctx, void **hwaccel_picture_pr
const AVPacketSideData *ff_get_coded_side_data(const AVCodecContext *avctx,
enum AVPacketSideDataType type);
+/**
+ * Skip samples in an AVFrame.
+ *
+ * @param skip amount of samples to skip unconditionally
+ */
+int ff_decode_skip_samples(AVCodecContext *avctx, AVFrame *frame,
+ uint32_t skip);
+
#endif /* AVCODEC_DECODE_H */
--
2.43.0