[FFmpeg-devel] [PATCHv2 2/3] ffplay: convert to new decode API

[Marton Balint]

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 | 96 +++++++++++++++++++++++++++++++++-------------------------------
 1 file changed, 49 insertions(+), 47 deletions(-)

diff --git a/ffplay.c b/ffplay.c
index cf138dc..e5120d7 100644
--- a/ffplay.c
+++ b/ffplay.c
@@ -187,7 +187,6 @@ enum {
 
 typedef struct Decoder {
     AVPacket pkt;
-    AVPacket pkt_temp;
     PacketQueue *queue;
     AVCodecContext *avctx;
     int pkt_serial;
@@ -551,40 +550,24 @@ 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 +576,8 @@ 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);
@@ -606,33 +589,52 @@ 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 (d->packet_pending) {
+                av_packet_move_ref(&pkt, &d->pkt);
+                d->packet_pending = 0;
+            } else {
+                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;
+                if (avcodec_send_packet(d->avctx, &pkt) == AVERROR(EAGAIN)) {
+                    av_log(d->avctx, AV_LOG_ERROR, "Receive_frame and send_packet both returned EAGAIN, which is an API violation.\n");
+                    d->packet_pending = 1;
+                    av_packet_move_ref(&d->pkt, &pkt);
                 }
             }
+            av_packet_unref(&pkt);
         }
-    } while (!got_frame && !d->finished);
-
-    return got_frame;
+    }
 }
 
 static void decoder_destroy(Decoder *d) {
-- 
2.10.2