Merge commit '061a0c14'

* commit '061a0c14':
  decode: restructure the core decoding code

CUVID decoder adapted by wm4.
Merged-by: James Almer <jamrial@gmail.com>

libavcodec/avcodec.h

@@ -3764,20 +3764,22 @@ typedef struct AVCodec {
     int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
     int (*close)(AVCodecContext *);
     /**
-     * Decode/encode API with decoupled packet/frame dataflow. The API is the
+     * Encode API with decoupled packet/frame dataflow. The API is the
      * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
      * that:
      * - never called if the codec is closed or the wrong type,
-     * - AVPacket parameter change side data is applied right before calling
-     *   AVCodec->send_packet,
-     * - if AV_CODEC_CAP_DELAY is not set, drain packets or frames are never sent,
-     * - only one drain packet is ever passed down (until the next flush()),
-     * - a drain AVPacket is always NULL (no need to check for avpkt->size).
+     * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
+     * - only one drain frame is ever passed down,
      */
     int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
-    int (*send_packet)(AVCodecContext *avctx, const AVPacket *avpkt);
-    int (*receive_frame)(AVCodecContext *avctx, AVFrame *frame);
     int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
+
+    /**
+     * Decode API with decoupled packet/frame dataflow. This function is called
+     * to get one output frame. It should call ff_decode_get_packet() to obtain
+     * input data.
+     */
+    int (*receive_frame)(AVCodecContext *avctx, AVFrame *frame);
     /**
      * Flush buffers.
      * Will be called when seeking

libavcodec/cuvid.c

@@ -31,6 +31,7 @@
 #include "libavutil/pixdesc.h"
 
 #include "avcodec.h"
+#include "decode.h"
 #include "internal.h"
 
 typedef struct CuvidContext
@@ -357,6 +358,13 @@ static int CUDAAPI cuvid_handle_picture_display(void *opaque, CUVIDPARSERDISPINF
     return 1;
 }
 
+static int cuvid_is_buffer_full(AVCodecContext *avctx)
+{
+    CuvidContext *ctx = avctx->priv_data;
+
+    return (av_fifo_size(ctx->frame_queue) / sizeof(CuvidParsedFrame)) + 2 > ctx->nb_surfaces;
+}
+
 static int cuvid_decode_packet(AVCodecContext *avctx, const AVPacket *avpkt)
 {
     CuvidContext *ctx = avctx->priv_data;
@@ -373,7 +381,7 @@ static int cuvid_decode_packet(AVCodecContext *avctx, const AVPacket *avpkt)
     if (is_flush && avpkt && avpkt->size)
         return AVERROR_EOF;
 
-    if ((av_fifo_size(ctx->frame_queue) / sizeof(CuvidParsedFrame)) + 2 > ctx->nb_surfaces && avpkt && avpkt->size)
+    if (cuvid_is_buffer_full(avctx) && avpkt && avpkt->size)
         return AVERROR(EAGAIN);
 
     if (ctx->bsf && avpkt && avpkt->size) {
@@ -464,6 +472,20 @@ static int cuvid_output_frame(AVCodecContext *avctx, AVFrame *frame)
             return ret;
     }
 
+    if (!cuvid_is_buffer_full(avctx)) {
+        AVPacket pkt = {0};
+        ret = ff_decode_get_packet(avctx, &pkt);
+        if (ret < 0 && ret != AVERROR_EOF)
+            return ret;
+        ret = cuvid_decode_packet(avctx, &pkt);
+        av_packet_unref(&pkt);
+        // cuvid_is_buffer_full() should avoid this.
+        if (ret == AVERROR(EAGAIN))
+            ret = AVERROR_EXTERNAL;
+        if (ret < 0 && ret != AVERROR_EOF)
+            return ret;
+    }
+
     ret = CHECK_CU(ctx->cudl->cuCtxPushCurrent(cuda_ctx));
     if (ret < 0)
         return ret;
@@ -1026,7 +1048,6 @@ static const AVOption options[] = {
         .init           = cuvid_decode_init, \
         .close          = cuvid_decode_end, \
         .decode         = cuvid_decode_frame, \
-        .send_packet    = cuvid_decode_packet, \
         .receive_frame  = cuvid_output_frame, \
         .flush          = cuvid_flush, \
         .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_AVOID_PROBING, \

libavcodec/decode.h

+/*
+ * generic decoding-related code
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_DECODE_H
+#define AVCODEC_DECODE_H
+
+/**
+ * Called by decoders to get the next packet for decoding.
+ *
+ * @param pkt An empty packet to be filled with data.
+ * @return 0 if a new reference has been successfully written to pkt
+ *         AVERROR(EAGAIN) if no data is currently available
+ *         AVERROR_EOF if and end of stream has been reached, so no more data
+ *                     will be available
+ */
+int ff_decode_get_packet(AVCodecContext *avctx, AVPacket *pkt);
+
+#endif /* AVCODEC_DECODE_H */

libavcodec/internal.h

@@ -101,6 +101,11 @@ typedef struct FramePool {
     int samples;
 } FramePool;
 
+typedef struct DecodeSimpleContext {
+    AVPacket *in_pkt;
+    AVFrame  *out_frame;
+} DecodeSimpleContext;
+
 typedef struct AVCodecInternal {
     /**
      * Whether the parent AVCodecContext is a copy of the context which had
@@ -137,6 +142,8 @@ typedef struct AVCodecInternal {
 
     void *thread_ctx;
 
+    DecodeSimpleContext ds;
+
     /**
      * Properties (timestamps+side data) extracted from the last packet passed
      * for decoding.
@@ -173,6 +180,17 @@ typedef struct AVCodecInternal {
     int buffer_pkt_valid; // encoding: packet without data can be valid
     AVFrame *buffer_frame;
     int draining_done;
+    /* set to 1 when the caller is using the old decoding API */
+    int compat_decode;
+    int compat_decode_warned;
+    /* this variable is set by the decoder internals to signal to the old
+     * API compat wrappers the amount of data consumed from the last packet */
+    size_t compat_decode_consumed;
+    /* when a partial packet has been consumed, this stores the remaining size
+     * of the packet (that should be submitted in the next decode call */
+    size_t compat_decode_partial_size;
+    AVFrame *compat_decode_frame;
+
     int showed_multi_packet_warning;
 
     int skip_samples_multiplier;

libavcodec/utils.c

@@ -172,7 +172,7 @@ int av_codec_is_encoder(const AVCodec *codec)
 
 int av_codec_is_decoder(const AVCodec *codec)
 {
-    return codec && (codec->decode || codec->send_packet);
+    return codec && (codec->decode || codec->receive_frame);
 }
 
 av_cold void avcodec_register(AVCodec *codec)
@@ -672,6 +672,12 @@ int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *code
         goto free_and_end;
     }
 
+    avctx->internal->compat_decode_frame = av_frame_alloc();
+    if (!avctx->internal->compat_decode_frame) {
+        ret = AVERROR(ENOMEM);
+        goto free_and_end;
+    }
+
     avctx->internal->buffer_frame = av_frame_alloc();
     if (!avctx->internal->buffer_frame) {
         ret = AVERROR(ENOMEM);
@@ -684,6 +690,12 @@ int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *code
         goto free_and_end;
     }
 
+    avctx->internal->ds.in_pkt = av_packet_alloc();
+    if (!avctx->internal->ds.in_pkt) {
+        ret = AVERROR(ENOMEM);
+        goto free_and_end;
+    }
+
     avctx->internal->last_pkt_props = av_packet_alloc();
     if (!avctx->internal->last_pkt_props) {
         ret = AVERROR(ENOMEM);
@@ -1114,9 +1126,13 @@ FF_ENABLE_DEPRECATION_WARNINGS
     av_freep(&avctx->priv_data);
     if (avctx->internal) {
         av_frame_free(&avctx->internal->to_free);
+        av_frame_free(&avctx->internal->compat_decode_frame);
         av_frame_free(&avctx->internal->buffer_frame);
         av_packet_free(&avctx->internal->buffer_pkt);
         av_packet_free(&avctx->internal->last_pkt_props);
+
+        av_packet_free(&avctx->internal->ds.in_pkt);
+
         av_freep(&avctx->internal->pool);
     }
     av_freep(&avctx->internal);
@@ -1163,9 +1179,13 @@ av_cold int avcodec_close(AVCodecContext *avctx)
         avctx->internal->byte_buffer_size = 0;
         av_freep(&avctx->internal->byte_buffer);
         av_frame_free(&avctx->internal->to_free);
+        av_frame_free(&avctx->internal->compat_decode_frame);
         av_frame_free(&avctx->internal->buffer_frame);
         av_packet_free(&avctx->internal->buffer_pkt);
         av_packet_free(&avctx->internal->last_pkt_props);
+
+        av_packet_free(&avctx->internal->ds.in_pkt);
+
         for (i = 0; i < FF_ARRAY_ELEMS(pool->pools); i++)
             av_buffer_pool_uninit(&pool->pools[i]);
         av_freep(&avctx->internal->pool);