decode: restructure the core decoding code
Currently, the new decoding API is pretty much just a wrapper around the
old deprecated one. This is problematic, since it interferes with making
full use of the flexibility added by the new API. The old API should
also be removed at some future point.
Reorganize the code so that the new send_packet/receive_frame functions
call the actual decoding directly and change the old deprecated
avcodec_decode_* functions into wrappers around the new API.
The new internal API for decoders is now changing as well. Before this
commit, it mirrors the public API, so the decoders need to implement
send_packet() and receive_frame() callbacks. This turns out to require
awkward constructs in both the decoders and the generic code. After this
commit, the decoders only implement the receive_frame() callback and
call a new internal function, ff_decode_get_packet() to obtain input
data, in the same manner to how the bitstream filters now work.
avcodec will now always make a reference to the input packet, which means
that non-refcounted input packets will be copied. Keeping the previous
behaviour, where this copy could sometimes be avoided, would make the
code significantly more complex and fragile for only dubious gains,
since packets are typically small and everyone who cares about
performance should use refcounted packets anyway.
8 years ago
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/*
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* generic decoding-related code
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*
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* This file is part of Libav.
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*
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* Libav is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* Libav is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with Libav; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#ifndef AVCODEC_DECODE_H
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#define AVCODEC_DECODE_H
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#include "libavutil/buffer.h"
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#include "libavutil/frame.h"
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#include "avcodec.h"
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/**
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* This struct stores per-frame lavc-internal data and is attached to it via
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* opaque_ref.
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*/
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typedef struct FrameDecodeData {
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/**
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* The original user-set opaque_ref.
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*/
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AVBufferRef *user_opaque_ref;
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/**
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* The callback to perform some delayed processing on the frame right
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* before it is returned to the caller.
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*
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* @note This code is called at some unspecified point after the frame is
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* returned from the decoder's decode/receive_frame call. Therefore it cannot rely
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* on AVCodecContext being in any specific state, so it does not get to
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* access AVCodecContext directly at all. All the state it needs must be
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* stored in the post_process_opaque object.
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*/
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int (*post_process)(void *logctx, AVFrame *frame);
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void *post_process_opaque;
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void (*post_process_opaque_free)(void *opaque);
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/**
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* Per-frame private data for hwaccels.
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*/
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void *hwaccel_priv;
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void (*hwaccel_priv_free)(void *priv);
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} FrameDecodeData;
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decode: restructure the core decoding code
Currently, the new decoding API is pretty much just a wrapper around the
old deprecated one. This is problematic, since it interferes with making
full use of the flexibility added by the new API. The old API should
also be removed at some future point.
Reorganize the code so that the new send_packet/receive_frame functions
call the actual decoding directly and change the old deprecated
avcodec_decode_* functions into wrappers around the new API.
The new internal API for decoders is now changing as well. Before this
commit, it mirrors the public API, so the decoders need to implement
send_packet() and receive_frame() callbacks. This turns out to require
awkward constructs in both the decoders and the generic code. After this
commit, the decoders only implement the receive_frame() callback and
call a new internal function, ff_decode_get_packet() to obtain input
data, in the same manner to how the bitstream filters now work.
avcodec will now always make a reference to the input packet, which means
that non-refcounted input packets will be copied. Keeping the previous
behaviour, where this copy could sometimes be avoided, would make the
code significantly more complex and fragile for only dubious gains,
since packets are typically small and everyone who cares about
performance should use refcounted packets anyway.
8 years ago
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/**
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* Called by decoders to get the next packet for decoding.
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*
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* @param pkt An empty packet to be filled with data.
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* @return 0 if a new reference has been successfully written to pkt
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* AVERROR(EAGAIN) if no data is currently available
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* AVERROR_EOF if and end of stream has been reached, so no more data
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* will be available
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*/
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int ff_decode_get_packet(AVCodecContext *avctx, AVPacket *pkt);
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void ff_decode_bsfs_uninit(AVCodecContext *avctx);
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decode: restructure the core decoding code
Currently, the new decoding API is pretty much just a wrapper around the
old deprecated one. This is problematic, since it interferes with making
full use of the flexibility added by the new API. The old API should
also be removed at some future point.
Reorganize the code so that the new send_packet/receive_frame functions
call the actual decoding directly and change the old deprecated
avcodec_decode_* functions into wrappers around the new API.
The new internal API for decoders is now changing as well. Before this
commit, it mirrors the public API, so the decoders need to implement
send_packet() and receive_frame() callbacks. This turns out to require
awkward constructs in both the decoders and the generic code. After this
commit, the decoders only implement the receive_frame() callback and
call a new internal function, ff_decode_get_packet() to obtain input
data, in the same manner to how the bitstream filters now work.
avcodec will now always make a reference to the input packet, which means
that non-refcounted input packets will be copied. Keeping the previous
behaviour, where this copy could sometimes be avoided, would make the
code significantly more complex and fragile for only dubious gains,
since packets are typically small and everyone who cares about
performance should use refcounted packets anyway.
8 years ago
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#endif /* AVCODEC_DECODE_H */
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