On 7/9/2023 6:48 AM, Anton Khirnov wrote:
Quoting James Almer (2023-07-08 21:00:36)
-/*
- * The core of the receive_frame_wrapper for the decoders implementing
- * the simple API. Certain decoders might consume partial packets without
- * returning any output, so this function needs to be called in a loop until it
- * returns EAGAIN.
- **/
-static inline int decode_simple_internal(AVCodecContext *avctx, AVFrame
*frame, int64_t *discarded_samples)
+static int discard_samples(AVCodecContext *avctx, AVFrame *frame, int64_t
*discarded_samples)
{
- AVCodecInternal *avci = avctx->internal;
- AVPacket *const pkt = avci->in_pkt;
- const FFCodec *const codec = ffcodec(avctx->codec);
- int got_frame, actual_got_frame;
- int ret;
-
- if (!pkt->data && !avci->draining) {
- av_packet_unref(pkt);
- ret = ff_decode_get_packet(avctx, pkt);
- if (ret < 0 && ret != AVERROR_EOF)
- return ret;
- }
-
- // Some codecs (at least wma lossless) will crash when feeding drain
packets
- // after EOF was signaled.
- if (avci->draining_done)
- return AVERROR_EOF;
-
- if (!pkt->data &&
- !(avctx->codec->capabilities & AV_CODEC_CAP_DELAY ||
- avctx->active_thread_type & FF_THREAD_FRAME))
- return AVERROR_EOF;
-
- got_frame = 0;
-
- if (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME) {
- ret = ff_thread_decode_frame(avctx, frame, &got_frame, pkt);
- } else {
- ret = codec->cb.decode(avctx, frame, &got_frame, pkt);
-
- if (!(codec->caps_internal & FF_CODEC_CAP_SETS_PKT_DTS))
- frame->pkt_dts = pkt->dts;
- if (avctx->codec->type == AVMEDIA_TYPE_VIDEO) {
-#if FF_API_FRAME_PKT
-FF_DISABLE_DEPRECATION_WARNINGS
- if(!avctx->has_b_frames)
- frame->pkt_pos = pkt->pos;
-FF_ENABLE_DEPRECATION_WARNINGS
-#endif
- //FIXME these should be under if(!avctx->has_b_frames)
- /* get_buffer is supposed to set frame parameters */
- if (!(avctx->codec->capabilities & AV_CODEC_CAP_DR1)) {
- if (!frame->sample_aspect_ratio.num) frame->sample_aspect_ratio
= avctx->sample_aspect_ratio;
- if (!frame->width) frame->width
= avctx->width;
- if (!frame->height) frame->height
= avctx->height;
- if (frame->format == AV_PIX_FMT_NONE) frame->format
= avctx->pix_fmt;
- }
- }
- }
- emms_c();
- actual_got_frame = got_frame;
+ AVCodecInternal *avci = avctx->internal;
+ int ret = 0;
if (avctx->codec->type == AVMEDIA_TYPE_VIDEO) {
if (frame->flags & AV_FRAME_FLAG_DISCARD)
- got_frame = 0;
+ ret = AVERROR(EAGAIN);
It's quite strange an unexpected for a function called discard_samples()
to do anything with video. By leaving video processing in the caller you
also save a level of indentation.
I could call it discard_samples_or_frame(), or discard_frame().
If i process the video in the caller, it will end up being duplicated in
patch 2, which goes against the point of factoring this out.
} else if (avctx->codec->type == AVMEDIA_TYPE_AUDIO) {
uint8_t *side;
size_t side_size;
@@ -359,16 +304,10 @@ FF_ENABLE_DEPRECATION_WARNINGS
uint8_t skip_reason = 0;
uint8_t discard_reason = 0;
- if (ret >= 0 && got_frame) {
if (frame->format == AV_SAMPLE_FMT_NONE)
frame->format = avctx->sample_fmt;
- if (!frame->ch_layout.nb_channels) {
- int ret2 = av_channel_layout_copy(&frame->ch_layout,
&avctx->ch_layout);
- if (ret2 < 0) {
- ret = ret2;
- got_frame = 0;
- }
- }
+ if (!frame->ch_layout.nb_channels)
+ ret = av_channel_layout_copy(&frame->ch_layout,
&avctx->ch_layout);
#if FF_API_OLD_CHANNEL_LAYOUT
FF_DISABLE_DEPRECATION_WARNINGS
if (!frame->channel_layout)
@@ -380,7 +319,6 @@ FF_ENABLE_DEPRECATION_WARNINGS
#endif
if (!frame->sample_rate)
frame->sample_rate = avctx->sample_rate;
- }
So the rest of the code below was previously executed even when there is
no frame? The change seems correct, but not I wouldn't expect it in a
'move' commit, so perhaps mention it in the commit message.
It still is, at least the block immediately after this, exporting
avci->skip_samples. I don't know how correct it is to do that, but i did
not want to change behavior in this set for decode() API decoders.
side= av_packet_get_side_data(avci->last_pkt_props, AV_PKT_DATA_SKIP_SAMPLES, &side_size);
if(side && side_size>=10) {
@@ -393,21 +331,21 @@ FF_ENABLE_DEPRECATION_WARNINGS
discard_reason = AV_RL8(side + 9);
}
- if ((frame->flags & AV_FRAME_FLAG_DISCARD) && got_frame &&
+ if ((frame->flags & AV_FRAME_FLAG_DISCARD) && !ret &&
!(avctx->flags2 & AV_CODEC_FLAG2_SKIP_MANUAL)) {
avci->skip_samples = FFMAX(0, avci->skip_samples -
frame->nb_samples);
- got_frame = 0;
*discarded_samples += frame->nb_samples;
+ ret = AVERROR(EAGAIN);
If I'm reading correctly, all the blocks below are conditioned on !ret,
so you might as well return here and drop those checks.
Ok.
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
