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14 * Lesser General Public License for more details.
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21#ifndef AVCODEC_CODEC_H
22#define AVCODEC_CODEC_H
34 * @addtogroup lavc_core
39 * Decoder can use draw_horiz_band callback.
41 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
43 * Codec uses get_buffer() or get_encode_buffer() for allocating buffers and
44 * supports custom allocators.
45 * If not set, it might not use get_buffer() or get_encode_buffer() at all, or
46 * use operations that assume the buffer was allocated by
47 * avcodec_default_get_buffer2 or avcodec_default_get_encode_buffer.
49 #define AV_CODEC_CAP_DR1 (1 << 1)
52 * Encoder can be reconfigured by passing new initialization parameters.
54 #define AV_CODEC_CAP_ENCODER_RECONF (1 << 2)
57 * Encoder or decoder requires flushing with NULL input at the end in order to
58 * give the complete and correct output.
60 * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
61 * with NULL data. The user can still send NULL data to the public encode
62 * or decode function, but libavcodec will not pass it along to the codec
63 * unless this flag is set.
66 * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
67 * avpkt->size=0 at the end to get the delayed data until the decoder no longer
71 * The encoder needs to be fed with NULL data at the end of encoding until the
72 * encoder no longer returns data.
74 * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
75 * flag also means that the encoder must set the pts and duration for
76 * each output packet. If this flag is not set, the pts and duration will
77 * be determined by libavcodec from the input frame.
79 #define AV_CODEC_CAP_DELAY (1 << 5)
81 * Codec can be fed a final frame with a smaller size.
82 * This can be used to prevent truncation of the last audio samples.
84 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
87 * Codec is experimental and is thus avoided in favor of non experimental
90 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
92 * Codec should fill in channel configuration and samplerate instead of container
94 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
96 * Codec supports frame-level multithreading.
98 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
100 * Codec supports slice-based (or partition-based) multithreading.
102 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
104 * Codec supports changed parameters at any point.
106 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
108 * Codec supports multithreading through a method other than slice- or
109 * frame-level multithreading. Typically this marks wrappers around
110 * multithreading-capable external libraries.
112 #define AV_CODEC_CAP_OTHER_THREADS (1 << 15)
114 * Audio encoder supports receiving a different number of samples in each call.
116 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
118 * Decoder is not a preferred choice for probing.
119 * This indicates that the decoder is not a good choice for probing.
120 * It could for example be an expensive to spin up hardware decoder,
121 * or it could simply not provide a lot of useful information about
123 * A decoder marked with this flag should only be used as last resort
124 * choice for probing.
126 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
129 * Codec is backed by a hardware implementation. Typically used to
130 * identify a non-hwaccel hardware decoder. For information about hwaccels, use
131 * avcodec_get_hw_config() instead.
133 #define AV_CODEC_CAP_HARDWARE (1 << 18)
136 * Codec is potentially backed by a hardware implementation, but not
137 * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
138 * implementation provides some sort of internal fallback.
140 #define AV_CODEC_CAP_HYBRID (1 << 19)
143 * This encoder can reorder user opaque values from input AVFrames and return
144 * them with corresponding output packets.
145 * @see AV_CODEC_FLAG_COPY_OPAQUE
147 #define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE (1 << 20)
150 * This encoder can be flushed using avcodec_flush_buffers(). If this flag is
151 * not set, the encoder must be closed and reopened to ensure that no frames
154 #define AV_CODEC_CAP_ENCODER_FLUSH (1 << 21)
157 * The encoder is able to output reconstructed frame data, i.e. raw frames that
158 * would be produced by decoding the encoded bitstream.
160 * Reconstructed frame output is enabled by the AV_CODEC_FLAG_RECON_FRAME flag.
162 #define AV_CODEC_CAP_ENCODER_RECON_FRAME (1 << 22)
169 const char *
name;
///< short name for the profile
177 * Name of the codec implementation.
178 * The name is globally unique among encoders and among decoders (but an
179 * encoder and a decoder can share the same name).
180 * This is the primary way to find a codec from the user perspective.
184 * Descriptive name for the codec, meant to be more human readable than name.
185 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
191 * Codec capabilities.
195 uint8_t
max_lowres;
///< maximum value for lowres supported by the decoder
198 const AVProfile *
profiles;
///< array of recognized profiles, or NULL if unknown, array is terminated by {AV_PROFILE_UNKNOWN}
201 * Group name of the codec implementation.
202 * This is a short symbolic name of the wrapper backing this codec. A
203 * wrapper uses some kind of external implementation for the codec, such
204 * as an external library, or a codec implementation provided by the OS or
206 * If this field is NULL, this is a builtin, libavcodec native codec.
207 * If non-NULL, this will be the suffix in AVCodec.name in most cases
208 * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
214 * Iterate over all registered codecs.
216 * @param opaque a pointer where libavcodec will store the iteration state. Must
217 * point to NULL to start the iteration.
219 * @return the next registered codec or NULL when the iteration is
225 * Find a registered decoder with a matching codec ID.
227 * @param id AVCodecID of the requested decoder
228 * @return A decoder if one was found, NULL otherwise.
233 * Find a registered decoder with the specified name.
235 * @param name name of the requested decoder
236 * @return A decoder if one was found, NULL otherwise.
241 * Find a registered encoder with a matching codec ID.
243 * @param id AVCodecID of the requested encoder
244 * @return An encoder if one was found, NULL otherwise.
249 * Find a registered encoder with the specified name.
251 * @param name name of the requested encoder
252 * @return An encoder if one was found, NULL otherwise.
256 * @return a non-zero number if codec is an encoder, zero otherwise
261 * @return a non-zero number if codec is a decoder, zero otherwise
266 * Return a name for the specified profile, if available.
268 * @param codec the codec that is searched for the given profile
269 * @param profile the profile value for which a name is requested
270 * @return A name for the profile if found, NULL otherwise.
276 * The codec supports this format via the hw_device_ctx interface.
278 * When selecting this format, AVCodecContext.hw_device_ctx should
279 * have been set to a device of the specified type before calling
284 * The codec supports this format via the hw_frames_ctx interface.
286 * When selecting this format for a decoder,
287 * AVCodecContext.hw_frames_ctx should be set to a suitable frames
288 * context inside the get_format() callback. The frames context
289 * must have been created on a device of the specified type.
291 * When selecting this format for an encoder,
292 * AVCodecContext.hw_frames_ctx should be set to the context which
293 * will be used for the input frames before calling avcodec_open2().
297 * The codec supports this format by some internal method.
299 * This format can be selected without any additional configuration -
300 * no device or frames context is required.
304 * The codec supports this format by some ad-hoc method.
306 * Additional settings and/or function calls are required. See the
307 * codec-specific documentation for details. (Methods requiring
308 * this sort of configuration are deprecated and others should be
309 * used in preference.)
316 * For decoders, a hardware pixel format which that decoder may be
317 * able to decode to if suitable hardware is available.
319 * For encoders, a pixel format which the encoder may be able to
320 * accept. If set to AV_PIX_FMT_NONE, this applies to all pixel
321 * formats supported by the codec.
325 * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
326 * setup methods which can be used with this configuration.
330 * The device type associated with the configuration.
332 * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
333 * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
339 * Retrieve supported hardware configurations for a codec.
341 * Values of index from zero to some maximum return the indexed configuration
342 * descriptor; all other values return NULL. If the codec does not support
343 * any hardware configurations then it will always return NULL.
351#endif /* AVCODEC_CODEC_H */
Convenience header that includes libavutil's core.
int av_codec_is_encoder(const AVCodec *codec)
int av_codec_is_decoder(const AVCodec *codec)
const AVCodec * avcodec_find_decoder(enum AVCodecID id)
Find a registered decoder with a matching codec ID.
const AVCodec * avcodec_find_decoder_by_name(const char *name)
Find a registered decoder with the specified name.
const AVCodec * avcodec_find_encoder(enum AVCodecID id)
Find a registered encoder with a matching codec ID.
AVCodecID
Identify the syntax and semantics of the bitstream.
const AVCodecHWConfig * avcodec_get_hw_config(const AVCodec *codec, int index)
Retrieve supported hardware configurations for a codec.
const AVCodec * avcodec_find_encoder_by_name(const char *name)
Find a registered encoder with the specified name.
const AVCodec * av_codec_iterate(void **opaque)
Iterate over all registered codecs.
const char * av_get_profile_name(const AVCodec *codec, int profile)
Return a name for the specified profile, if available.
@ AV_CODEC_HW_CONFIG_METHOD_AD_HOC
The codec supports this format by some ad-hoc method.
@ AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX
The codec supports this format via the hw_frames_ctx interface.
@ AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX
The codec supports this format via the hw_device_ctx interface.
@ AV_CODEC_HW_CONFIG_METHOD_INTERNAL
The codec supports this format by some internal method.
AVPixelFormat
Pixel format.
Describe the class of an AVClass context structure.
enum AVHWDeviceType device_type
The device type associated with the configuration.
int methods
Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible setup methods which can be used...
enum AVPixelFormat pix_fmt
For decoders, a hardware pixel format which that decoder may be able to decode to if suitable hardwar...
const AVClass * priv_class
AVClass for the private context.
const AVProfile * profiles
array of recognized profiles, or NULL if unknown, array is terminated by {AV_PROFILE_UNKNOWN}
const char * long_name
Descriptive name for the codec, meant to be more human readable than name.
const char * wrapper_name
Group name of the codec implementation.
const char * name
Name of the codec implementation.
int capabilities
Codec capabilities.
uint8_t max_lowres
maximum value for lowres supported by the decoder
const char * name
short name for the profile