[FFmpeg-devel] [PATCH 2/3] ffplay: convert to new decode API

Marton Balint cus at passwd.hu
Wed Mar 15 04:47:57 EET 2017


Since subtitles are not yet supported with the new API, CODEC_CAP_DELAY
subtitle codecs (only libzvbi so far) may loose the last few buffered frames in
the end of the stream.

The impact of this is so limited, it seemded better to accept it than losing
the simplification benefits of the new API.

Signed-off-by: Marton Balint <cus at passwd.hu>
---
 ffplay.c | 92 +++++++++++++++++++++++++++++-----------------------------------
 1 file changed, 41 insertions(+), 51 deletions(-)

diff --git a/ffplay.c b/ffplay.c
index cf138dc..06d1d22 100644
--- a/ffplay.c
+++ b/ffplay.c
@@ -186,13 +186,10 @@ enum {
 };
 
 typedef struct Decoder {
-    AVPacket pkt;
-    AVPacket pkt_temp;
     PacketQueue *queue;
     AVCodecContext *avctx;
     int pkt_serial;
     int finished;
-    int packet_pending;
     SDL_cond *empty_queue_cond;
     int64_t start_pts;
     AVRational start_pts_tb;
@@ -551,40 +548,24 @@ static void decoder_init(Decoder *d, AVCodecContext *avctx, PacketQueue *queue,
     d->queue = queue;
     d->empty_queue_cond = empty_queue_cond;
     d->start_pts = AV_NOPTS_VALUE;
+    d->pkt_serial = -1;
 }
 
 static int decoder_decode_frame(Decoder *d, AVFrame *frame, AVSubtitle *sub) {
-    int got_frame = 0;
+    int ret = AVERROR(EAGAIN);
 
-    do {
-        int ret = -1;
+    for (;;) {
+        AVPacket pkt;
 
+        if (d->queue->serial == d->pkt_serial) {
+        do {
         if (d->queue->abort_request)
             return -1;
 
-        if (!d->packet_pending || d->queue->serial != d->pkt_serial) {
-            AVPacket pkt;
-            do {
-                if (d->queue->nb_packets == 0)
-                    SDL_CondSignal(d->empty_queue_cond);
-                if (packet_queue_get(d->queue, &pkt, 1, &d->pkt_serial) < 0)
-                    return -1;
-                if (pkt.data == flush_pkt.data) {
-                    avcodec_flush_buffers(d->avctx);
-                    d->finished = 0;
-                    d->next_pts = d->start_pts;
-                    d->next_pts_tb = d->start_pts_tb;
-                }
-            } while (pkt.data == flush_pkt.data || d->queue->serial != d->pkt_serial);
-            av_packet_unref(&d->pkt);
-            d->pkt_temp = d->pkt = pkt;
-            d->packet_pending = 1;
-        }
-
         switch (d->avctx->codec_type) {
             case AVMEDIA_TYPE_VIDEO:
-                ret = avcodec_decode_video2(d->avctx, frame, &got_frame, &d->pkt_temp);
-                if (got_frame) {
+                ret = avcodec_receive_frame(d->avctx, frame);
+                if (ret >= 0) {
                     if (decoder_reorder_pts == -1) {
                         frame->pts = av_frame_get_best_effort_timestamp(frame);
                     } else if (!decoder_reorder_pts) {
@@ -593,8 +574,8 @@ static int decoder_decode_frame(Decoder *d, AVFrame *frame, AVSubtitle *sub) {
                 }
                 break;
             case AVMEDIA_TYPE_AUDIO:
-                ret = avcodec_decode_audio4(d->avctx, frame, &got_frame, &d->pkt_temp);
-                if (got_frame) {
+                ret = avcodec_receive_frame(d->avctx, frame);
+                if (ret >= 0) {
                     AVRational tb = (AVRational){1, frame->sample_rate};
                     if (frame->pts != AV_NOPTS_VALUE)
                         frame->pts = av_rescale_q(frame->pts, av_codec_get_pkt_timebase(d->avctx), tb);
@@ -606,37 +587,46 @@ static int decoder_decode_frame(Decoder *d, AVFrame *frame, AVSubtitle *sub) {
                     }
                 }
                 break;
-            case AVMEDIA_TYPE_SUBTITLE:
-                ret = avcodec_decode_subtitle2(d->avctx, sub, &got_frame, &d->pkt_temp);
-                break;
+        }
+        if (ret == AVERROR_EOF) {
+            d->finished = d->pkt_serial;
+            avcodec_flush_buffers(d->avctx);
+            return 0;
+        }
+        if (ret >= 0)
+            return 1;
+        } while (ret != AVERROR(EAGAIN));
         }
 
-        if (ret < 0) {
-            d->packet_pending = 0;
+        do {
+            if (d->queue->nb_packets == 0)
+                SDL_CondSignal(d->empty_queue_cond);
+            if (packet_queue_get(d->queue, &pkt, 1, &d->pkt_serial) < 0)
+                return -1;
+        } while (d->queue->serial != d->pkt_serial);
+
+        if (pkt.data == flush_pkt.data) {
+            avcodec_flush_buffers(d->avctx);
+            d->finished = 0;
+            d->next_pts = d->start_pts;
+            d->next_pts_tb = d->start_pts_tb;
         } else {
-            d->pkt_temp.dts =
-            d->pkt_temp.pts = AV_NOPTS_VALUE;
-            if (d->pkt_temp.data) {
-                if (d->avctx->codec_type != AVMEDIA_TYPE_AUDIO)
-                    ret = d->pkt_temp.size;
-                d->pkt_temp.data += ret;
-                d->pkt_temp.size -= ret;
-                if (d->pkt_temp.size <= 0)
-                    d->packet_pending = 0;
+            if (d->avctx->codec_type == AVMEDIA_TYPE_SUBTITLE) {
+                int got_frame = 0;
+                ret = avcodec_decode_subtitle2(d->avctx, sub, &got_frame, &pkt);
+                if (ret < 0)
+                    ret = AVERROR(EAGAIN);
+                else
+                    ret = got_frame ? 0 : (pkt.data ? AVERROR(EAGAIN) : AVERROR_EOF);
             } else {
-                if (!got_frame) {
-                    d->packet_pending = 0;
-                    d->finished = d->pkt_serial;
-                }
+                av_assert0(avcodec_send_packet(d->avctx, &pkt) != AVERROR(EAGAIN));
             }
+            av_packet_unref(&pkt);
         }
-    } while (!got_frame && !d->finished);
-
-    return got_frame;
+    }
 }
 
 static void decoder_destroy(Decoder *d) {
-    av_packet_unref(&d->pkt);
     avcodec_free_context(&d->avctx);
 }
 
-- 
2.10.2



More information about the ffmpeg-devel mailing list