2 * Copyright (c) 2010 The VP8 project authors. All Rights Reserved.
4 * Use of this source code is governed by a BSD-style license and patent
5 * grant that can be found in the LICENSE file in the root of the source
6 * tree. All contributing project authors may be found in the AUTHORS
7 * file in the root of the source tree.
11 /*!\defgroup encoder Encoder Algorithm Interface
13 * This abstraction allows applications using this encoder to easily support
14 * multiple video formats with minimal code duplication. This section describes
15 * the interface common to all encoders.
19 /*!\file vpx_encoder.h
20 * \brief Describes the encoder algorithm interface to applications.
22 * This file describes the interface between an application and a
23 * video encoder algorithm.
32 #include "vpx_codec.h"
35 /*!\brief Current ABI version number
38 * If this file is altered in any way that changes the ABI, this value
39 * must be bumped. Examples include, but are not limited to, changing
40 * types, removing or reassigning enums, adding/removing/rearranging
41 * fields to structures
43 #define VPX_ENCODER_ABI_VERSION (2 + VPX_CODEC_ABI_VERSION) /**<\hideinitializer*/
46 /*! \brief Encoder capabilities bitfield
48 * Each encoder advertises the capabilities it supports as part of its
49 * ::vpx_codec_iface_t interface structure. Capabilities are extra
50 * interfaces or functionality, and are not required to be supported
53 * The available flags are specifiedby VPX_CODEC_CAP_* defines.
55 #define VPX_CODEC_CAP_PSNR 0x10000 /**< Can issue PSNR packets */
58 /*! \brief Initialization-time Feature Enabling
60 * Certain codec features must be known at initialization time, to allow
61 * for proper memory allocation.
63 * The available flags are specified by VPX_CODEC_USE_* defines.
65 #define VPX_CODEC_USE_PSNR 0x10000 /**< Calculate PSNR on each frame */
68 /*!\brief Generic fixed size buffer structure
70 * This structure is able to hold a reference to any fixed size buffer.
72 typedef struct vpx_fixed_buf
74 void *buf; /**< Pointer to the data */
75 size_t sz; /**< Length of the buffer, in chars */
76 } vpx_fixed_buf_t; /**< alias for struct vpx_fixed_buf */
79 /*!\brief Time Stamp Type
81 * An integer, which when multiplied by the stream's time base, provides
82 * the absolute time of a sample.
84 typedef int64_t vpx_codec_pts_t;
87 /*!\brief Compressed Frame Flags
89 * This type represents a bitfield containing information about a compressed
90 * frame that may be useful to an application. The most significant 16 bits
91 * can be used by an algorithm to provide additional detail, for example to
92 * support frame types that are codec specific (MPEG-1 D-frames for example)
94 typedef uint32_t vpx_codec_frame_flags_t;
95 #define VPX_FRAME_IS_KEY 0x1 /**< frame is the start of a GOP */
96 #define VPX_FRAME_IS_DROPPABLE 0x2 /**< frame can be dropped without affecting
97 the stream (no future frame depends on
99 #define VPX_FRAME_IS_INVISIBLE 0x4 /**< frame should be decoded but will not
103 /*!\brief Encoder output packet variants
105 * This enumeration lists the different kinds of data packets that can be
106 * returned by calls to vpx_codec_get_cx_data(). Algorithms \ref MAY
107 * extend this list to provide additional functionality.
109 enum vpx_codec_cx_pkt_kind
111 VPX_CODEC_CX_FRAME_PKT, /**< Compressed video frame */
112 VPX_CODEC_STATS_PKT, /**< Two-pass statistics for this frame */
113 VPX_CODEC_PSNR_PKT, /**< PSNR statistics for this frame */
114 VPX_CODEC_CUSTOM_PKT = 256 /**< Algorithm extensions */
118 /*!\brief Encoder output packet
120 * This structure contains the different kinds of output data the encoder
121 * may produce while compressing a frame.
123 typedef struct vpx_codec_cx_pkt
125 enum vpx_codec_cx_pkt_kind kind; /**< packet variant */
130 void *buf; /**< compressed data buffer */
131 size_t sz; /**< length of compressed data */
132 vpx_codec_pts_t pts; /**< time stamp to show frame
133 (in timebase units) */
134 unsigned long duration; /**< duration to show frame
135 (in timebase units) */
136 vpx_codec_frame_flags_t flags; /**< flags for this frame */
137 } frame; /**< data for compressed frame packet */
138 struct vpx_fixed_buf twopass_stats; /**< data for two-pass packet */
141 unsigned int samples[4]; /**< Number of samples, total/y/u/v */
142 uint64_t sse[4]; /**< sum squared error, total/y/u/v */
143 double psnr[4]; /**< PSNR, total/y/u/v */
144 } psnr; /**< data for PSNR packet */
145 struct vpx_fixed_buf raw; /**< data for arbitrary packets */
147 /* This packet size is fixed to allow codecs to extend this
148 * interface without having to manage storage for raw packets,
149 * ie if it's smaller than 128 bytes, you can store in the
150 * packet list directly.
152 char pad[128 - sizeof(enum vpx_codec_cx_pkt_kind)]; /**< fixed sz */
153 } data; /**< packet data */
154 } vpx_codec_cx_pkt_t; /**< alias for struct vpx_codec_cx_pkt */
157 /*!\brief Rational Number
159 * This structure holds a fractional value.
161 typedef struct vpx_rational
163 int num; /**< fraction numerator */
164 int den; /**< fraction denominator */
165 } vpx_rational_t; /**< alias for struct vpx_rational */
168 /*!\brief Multi-pass Encoding Pass */
171 VPX_RC_ONE_PASS, /**< Single pass mode */
172 VPX_RC_FIRST_PASS, /**< First pass of multi-pass mode */
173 VPX_RC_LAST_PASS, /**< Final pass of multi-pass mode */
177 /*!\brief Rate control mode */
180 VPX_VBR, /**< Variable Bit Rate (VBR) mode */
181 VPX_CBR /**< Constant Bit Rate (CBR) mode */
185 /*!\brief Keyframe placement mode.
187 * This enumeration determines whether keyframes are placed automatically by
188 * the encoder or whether this behavior is disabled. Older releases of this
189 * SDK were implemented such that VPX_KF_FIXED meant keyframes were disabled.
190 * This name is confusing for this behavior, so the new symbols to be used
191 * are VPX_KF_AUTO and VPX_KF_DISABLED.
195 VPX_KF_FIXED, /**< deprecated, implies VPX_KF_DISABLED */
196 VPX_KF_AUTO, /**< Encoder determines optimal placement automatically */
197 VPX_KF_DISABLED = 0 /**< Encoder does not place keyframes. */
201 /*!\brief Encoded Frame Flags
203 * This type indicates a bitfield to be passed to vpx_codec_encode(), defining
204 * per-frame boolean values. By convention, bits common to all codecs will be
205 * named VPX_EFLAG_*, and bits specific to an algorithm will be named
206 * /algo/_eflag_*. The lower order 16 bits are reserved for common use.
208 typedef long vpx_enc_frame_flags_t;
209 #define VPX_EFLAG_FORCE_KF (1<<0) /**< Force this frame to be a keyframe */
212 /*!\brief Encoder configuration structure
214 * This structure contains the encoder settings that have common representations
215 * across all codecs. This doesn't imply that all codecs support all features,
218 typedef struct vpx_codec_enc_cfg
221 * generic settings (g)
224 /*!\brief Algorithm specific "usage" value
226 * Algorithms may define multiple values for usage, which may convey the
227 * intent of how the application intends to use the stream. If this value
228 * is non-zero, consult the documentation for the codec to determine its
231 unsigned int g_usage;
234 /*!\brief Maximum number of threads to use
236 * For multi-threaded implementations, use no more than this number of
237 * threads. The codec may use fewer threads than allowed. The value
238 * 0 is equivalent to the value 1.
240 unsigned int g_threads;
243 /*!\brief Bitstream profile to use
245 * Some codecs support a notion of multiple bitstream profiles. Typically
246 * this maps to a set of features that are turned on or off. Often the
247 * profile to use is determined by the features of the intended decoder.
248 * Consult the documentation for the codec to determine the valid values
249 * for this parameter, or set to zero for a sane default.
251 unsigned int g_profile; /**< profile of bitstream to use */
255 /*!\brief Width of the frame
257 * This value identifies the presentation resolution of the frame,
258 * in pixels. Note that the frames passed as input to the encoder must
259 * have this resolution. Frames will be presented by the decoder in this
260 * resolution, independent of any spatial resampling the encoder may do.
265 /*!\brief Height of the frame
267 * This value identifies the presentation resolution of the frame,
268 * in pixels. Note that the frames passed as input to the encoder must
269 * have this resolution. Frames will be presented by the decoder in this
270 * resolution, independent of any spatial resampling the encoder may do.
275 /*!\brief Stream timebase units
277 * Indicates the smallest interval of time, in seconds, used by the stream.
278 * For fixed frame rate material, or variable frame rate material where
279 * frames are timed at a multiple of a given clock (ex: video capture),
280 * the \ref RECOMMENDED method is to set the timebase to the reciprocal
281 * of the frame rate (ex: 1001/30000 for 29.970 Hz NTSC). This allows the
282 * pts to correspond to the frame number, which can be handy. For
283 * re-encoding video from containers with absolute time timestamps, the
284 * \ref RECOMMENDED method is to set the timebase to that of the parent
285 * container or multimedia framework (ex: 1/1000 for ms, as in FLV).
287 struct vpx_rational g_timebase;
290 /*!\brief Enable error resilient mode.
292 * Error resilient mode indicates to the encoder that it should take
293 * measures appropriate for streaming over lossy or noisy links, if
294 * possible. Set to 1 to enable this feature, 0 to disable it.
296 unsigned int g_error_resilient;
299 /*!\brief Multi-pass Encoding Mode
301 * This value should be set to the current phase for multi-pass encoding.
302 * For single pass, set to #VPX_RC_ONE_PASS.
304 enum vpx_enc_pass g_pass;
307 /*!\brief Allow lagged encoding
309 * If set, this value allows the encoder to consume a number of input
310 * frames before producing output frames. This allows the encoder to
311 * base decisions for the current frame on future frames. This does
312 * increase the latency of the encoding pipeline, so it is not appropriate
313 * in all situations (ex: realtime encoding).
315 * Note that this is a maximum value -- the encoder may produce frames
316 * sooner than the given limit. Set this value to 0 to disable this
319 unsigned int g_lag_in_frames;
323 * rate control settings (rc)
326 /*!\brief Temporal resampling configuration, if supported by the codec.
328 * Temporal resampling allows the codec to "drop" frames as a strategy to
329 * meet its target data rate. This can cause temporal discontinuities in
330 * the encoded video, which may appear as stuttering during playback. This
331 * trade-off is often acceptable, but for many applications is not. It can
332 * be disabled in these cases.
334 * Note that not all codecs support this feature. All vpx VPx codecs do.
335 * For other codecs, consult the documentation for that algorithm.
337 * This threshold is described as a percentage of the target data buffer.
338 * When the data buffer falls below this percentage of fullness, a
339 * dropped frame is indicated. Set the threshold to zero (0) to disable
342 unsigned int rc_dropframe_thresh;
345 /*!\brief Enable/disable spatial resampling, if supported by the codec.
347 * Spatial resampling allows the codec to compress a lower resolution
348 * version of the frame, which is then upscaled by the encoder to the
349 * correct presentation resolution. This increases visual quality at
350 * low data rates, at the expense of CPU time on the encoder/decoder.
352 unsigned int rc_resize_allowed;
355 /*!\brief Spatial resampling up watermark.
357 * This threshold is described as a percentage of the target data buffer.
358 * When the data buffer rises above this percentage of fullness, the
359 * encoder will step up to a higher resolution version of the frame.
361 unsigned int rc_resize_up_thresh;
364 /*!\brief Spatial resampling down watermark.
366 * This threshold is described as a percentage of the target data buffer.
367 * When the data buffer falls below this percentage of fullness, the
368 * encoder will step down to a lower resolution version of the frame.
370 unsigned int rc_resize_down_thresh;
373 /*!\brief Rate control algorithm to use.
375 * Indicates whether the end usage of this stream is to be streamed over
376 * a bandwidth constrained link, indicating that Constant Bit Rate (CBR)
377 * mode should be used, or whether it will be played back on a high
378 * bandwidth link, as from a local disk, where higher variations in
379 * bitrate are acceptable.
381 enum vpx_rc_mode rc_end_usage;
384 /*!\brief Two-pass stats buffer.
386 * A buffer containing all of the stats packets produced in the first
387 * pass, concatenated.
389 struct vpx_fixed_buf rc_twopass_stats_in;
392 /*!\brief Target data rate
394 * Target bandwidth to use for this stream, in kilobits per second.
396 unsigned int rc_target_bitrate;
404 /*!\brief Minimum (Best Quality) Quantizer
406 * The quantizer is the most direct control over the quality of the
407 * encoded image. The range of valid values for the quantizer is codec
408 * specific. Consult the documentation for the codec to determine the
409 * values to use. To determine the range programmatically, call
410 * vpx_codec_enc_config_default() with a usage value of 0.
412 unsigned int rc_min_quantizer;
415 /*!\brief Maximum (Worst Quality) Quantizer
417 * The quantizer is the most direct control over the quality of the
418 * encoded image. The range of valid values for the quantizer is codec
419 * specific. Consult the documentation for the codec to determine the
420 * values to use. To determine the range programmatically, call
421 * vpx_codec_enc_config_default() with a usage value of 0.
423 unsigned int rc_max_quantizer;
431 /*!\brief Rate control undershoot tolerance
433 * This value, expressed as a percentage of the target bitrate, describes
434 * the target bitrate for easier frames, allowing bits to be saved for
435 * harder frames. Set to zero to use the codec default.
437 unsigned int rc_undershoot_pct;
440 /*!\brief Rate control overshoot tolerance
442 * This value, expressed as a percentage of the target bitrate, describes
443 * the maximum allowed bitrate for a given frame. Set to zero to use the
446 unsigned int rc_overshoot_pct;
450 * decoder buffer model parameters
454 /*!\brief Decoder Buffer Size
456 * This value indicates the amount of data that may be buffered by the
457 * decoding application. Note that this value is expressed in units of
458 * time (milliseconds). For example, a value of 5000 indicates that the
459 * client will buffer (at least) 5000ms worth of encoded data. Use the
460 * target bitrate (#rc_target_bitrate) to convert to bits/bytes, if
463 unsigned int rc_buf_sz;
466 /*!\brief Decoder Buffer Initial Size
468 * This value indicates the amount of data that will be buffered by the
469 * decoding application prior to beginning playback. This value is
470 * expressed in units of time (milliseconds). Use the target bitrate
471 * (#rc_target_bitrate) to convert to bits/bytes, if necessary.
473 unsigned int rc_buf_initial_sz;
476 /*!\brief Decoder Buffer Optimal Size
478 * This value indicates the amount of data that the encoder should try
479 * to maintain in the decoder's buffer. This value is expressed in units
480 * of time (milliseconds). Use the target bitrate (#rc_target_bitrate)
481 * to convert to bits/bytes, if necessary.
483 unsigned int rc_buf_optimal_sz;
487 * 2 pass rate control parameters
491 /*!\brief Two-pass mode CBR/VBR bias
493 * Bias, expressed on a scale of 0 to 100, for determining target size
494 * for the current frame. The value 0 indicates the optimal CBR mode
495 * value should be used. The value 100 indicates the optimal VBR mode
496 * value should be used. Values in between indicate which way the
497 * encoder should "lean."
499 unsigned int rc_2pass_vbr_bias_pct; /**< RC mode bias between CBR and VBR(0-100: 0->CBR, 100->VBR) */
502 /*!\brief Two-pass mode per-GOP minimum bitrate
504 * This value, expressed as a percentage of the target bitrate, indicates
505 * the minimum bitrate to be used for a single GOP (aka "section")
507 unsigned int rc_2pass_vbr_minsection_pct;
510 /*!\brief Two-pass mode per-GOP maximum bitrate
512 * This value, expressed as a percentage of the target bitrate, indicates
513 * the maximum bitrate to be used for a single GOP (aka "section")
515 unsigned int rc_2pass_vbr_maxsection_pct;
519 * keyframing settings (kf)
522 /*!\brief Keyframe placement mode
524 * This value indicates whether the encoder should place keyframes at a
525 * fixed interval, or determine the optimal placement automatically
526 * (as governed by the #kf_min_dist and #kf_max_dist parameters)
528 enum vpx_kf_mode kf_mode;
531 /*!\brief Keyframe minimum interval
533 * This value, expressed as a number of frames, prevents the encoder from
534 * placing a keyframe nearer than kf_min_dist to the previous keyframe. At
535 * least kf_min_dist frames non-keyframes will be coded before the next
536 * keyframe. Set kf_min_dist equal to kf_max_dist for a fixed interval.
538 unsigned int kf_min_dist;
541 /*!\brief Keyframe maximum interval
543 * This value, expressed as a number of frames, forces the encoder to code
544 * a keyframe if one has not been coded in the last kf_max_dist frames.
545 * A value of 0 implies all frames will be keyframes. Set kf_min_dist
546 * equal to kf_max_dist for a fixed interval.
548 unsigned int kf_max_dist;
550 } vpx_codec_enc_cfg_t; /**< alias for struct vpx_codec_enc_cfg */
553 /*!\brief Initialize an encoder instance
555 * Initializes a encoder context using the given interface. Applications
556 * should call the vpx_codec_enc_init convenience macro instead of this
557 * function directly, to ensure that the ABI version number parameter
558 * is properly initialized.
560 * In XMA mode (activated by setting VPX_CODEC_USE_XMA in the flags
561 * parameter), the storage pointed to by the cfg parameter must be
562 * kept readable and stable until all memory maps have been set.
564 * \param[in] ctx Pointer to this instance's context.
565 * \param[in] iface Pointer to the algorithm interface to use.
566 * \param[in] cfg Configuration to use, if known. May be NULL.
567 * \param[in] flags Bitfield of VPX_CODEC_USE_* flags
568 * \param[in] ver ABI version number. Must be set to
569 * VPX_ENCODER_ABI_VERSION
570 * \retval #VPX_CODEC_OK
571 * The decoder algorithm initialized.
572 * \retval #VPX_CODEC_MEM_ERROR
573 * Memory allocation failed.
575 vpx_codec_err_t vpx_codec_enc_init_ver(vpx_codec_ctx_t *ctx,
576 vpx_codec_iface_t *iface,
577 vpx_codec_enc_cfg_t *cfg,
578 vpx_codec_flags_t flags,
582 /*!\brief Convenience macro for vpx_codec_enc_init_ver()
584 * Ensures the ABI version parameter is properly set.
586 #define vpx_codec_enc_init(ctx, iface, cfg, flags) \
587 vpx_codec_enc_init_ver(ctx, iface, cfg, flags, VPX_ENCODER_ABI_VERSION)
590 /*!\brief Get a default configuration
592 * Initializes a encoder configuration structure with default values. Supports
593 * the notion of "usages" so that an algorithm may offer different default
594 * settings depending on the user's intended goal. This function \ref SHOULD
595 * be called by all applications to initialize the configuration structure
596 * before specializing the configuration with application specific values.
598 * \param[in] iface Pointer to the algorithm interface to use.
599 * \param[out] cfg Configuration buffer to populate
600 * \param[in] usage End usage. Set to 0 or use codec specific values.
602 * \retval #VPX_CODEC_OK
603 * The configuration was populated.
604 * \retval #VPX_CODEC_INCAPABLE
605 * Interface is not an encoder interface.
606 * \retval #VPX_CODEC_INVALID_PARAM
607 * A parameter was NULL, or the usage value was not recognized.
609 vpx_codec_err_t vpx_codec_enc_config_default(vpx_codec_iface_t *iface,
610 vpx_codec_enc_cfg_t *cfg,
614 /*!\brief Set or change configuration
616 * Reconfigures an encoder instance according to the given configuration.
618 * \param[in] ctx Pointer to this instance's context
619 * \param[in] cfg Configuration buffer to use
621 * \retval #VPX_CODEC_OK
622 * The configuration was populated.
623 * \retval #VPX_CODEC_INCAPABLE
624 * Interface is not an encoder interface.
625 * \retval #VPX_CODEC_INVALID_PARAM
626 * A parameter was NULL, or the usage value was not recognized.
628 vpx_codec_err_t vpx_codec_enc_config_set(vpx_codec_ctx_t *ctx,
629 const vpx_codec_enc_cfg_t *cfg);
632 /*!\brief Get global stream headers
634 * Retrieves a stream level global header packet, if supported by the codec.
636 * \param[in] ctx Pointer to this instance's context
639 * Encoder does not support global header
641 * Pointer to buffer containing global header packet
643 vpx_fixed_buf_t *vpx_codec_get_global_headers(vpx_codec_ctx_t *ctx);
646 #define VPX_DL_REALTIME (1) /**< deadline parameter analogous to
647 * VPx REALTIME mode. */
648 #define VPX_DL_GOOD_QUALITY (1000000) /**< deadline parameter analogous to
649 * VPx GOOD QUALITY mode. */
650 #define VPX_DL_BEST_QUALITY (0) /**< deadline parameter analogous to
651 * VPx BEST QUALITY mode. */
652 /*!\brief Encode a frame
654 * Encodes a video frame at the given "presentation time." The presentation
655 * time stamp (PTS) \ref MUST be strictly increasing.
657 * The encoder supports the notion of a soft real-time deadline. Given a
658 * non-zero value to the deadline parameter, the encoder will make a "best
659 * effort" guarantee to return before the given time slice expires. It is
660 * implicit that limiting the available time to encode will degrade the
661 * output quality. The encoder can be given an unlimited time to produce the
662 * best possible frame by specifying a deadline of '0'. This deadline
663 * supercedes the VPx notion of "best quality, good quality, realtime".
664 * Applications that wish to map these former settings to the new deadline
665 * based system can use the symbols #VPX_DL_REALTIME, #VPX_DL_GOOD_QUALITY,
666 * and #VPX_DL_BEST_QUALITY.
668 * When the last frame has been passed to the encoder, this function should
669 * continue to be called, with the img parameter set to NULL. This will
670 * signal the end-of-stream condition to the encoder and allow it to encode
671 * any held buffers. Encoding is complete when vpx_codec_encode() is called
672 * and vpx_codec_get_cx_data() returns no data.
674 * \param[in] ctx Pointer to this instance's context
675 * \param[in] img Image data to encode, NULL to flush.
676 * \param[in] pts Presentation time stamp, in timebase units.
677 * \param[in] duration Duration to show frame, in timebase units.
678 * \param[in] flags Flags to use for encoding this frame.
679 * \param[in] deadline Time to spend encoding, in microseconds. (0=infinite)
681 * \retval #VPX_CODEC_OK
682 * The configuration was populated.
683 * \retval #VPX_CODEC_INCAPABLE
684 * Interface is not an encoder interface.
685 * \retval #VPX_CODEC_INVALID_PARAM
686 * A parameter was NULL, the image format is unsupported, etc.
688 vpx_codec_err_t vpx_codec_encode(vpx_codec_ctx_t *ctx,
689 const vpx_image_t *img,
691 unsigned long duration,
692 vpx_enc_frame_flags_t flags,
693 unsigned long deadline);
696 /*!\brief Set compressed data output buffer
698 * Sets the buffer that the codec should output the compressed data
699 * into. This call effectively sets the buffer pointer returned in the
700 * next VPX_CODEC_CX_FRAME_PKT packet. Subsequent packets will be
701 * appended into this buffer. The buffer is preserved across frames,
702 * so applications must periodically call this function after flushing
703 * the accumulated compressed data to disk or to the network to reset
704 * the pointer to the buffer's head.
706 * `pad_before` bytes will be skipped before writing the compressed
707 * data, and `pad_after` bytes will be appended to the packet. The size
708 * of the packet will be the sum of the size of the actual compressed
709 * data, pad_before, and pad_after. The padding bytes will be preserved
712 * Note that calling this function does not guarantee that the returned
713 * compressed data will be placed into the specified buffer. In the
714 * event that the encoded data will not fit into the buffer provided,
715 * the returned packet \ref MAY point to an internal buffer, as it would
716 * if this call were never used. In this event, the output packet will
717 * NOT have any padding, and the application must free space and copy it
718 * to the proper place. This is of particular note in configurations
719 * that may output multiple packets for a single encoded frame (e.g., lagged
720 * encoding) or if the application does not reset the buffer periodically.
722 * Applications may restore the default behavior of the codec providing
723 * the compressed data buffer by calling this function with a NULL
726 * Applications \ref MUSTNOT call this function during iteration of
727 * vpx_codec_get_cx_data().
729 * \param[in] ctx Pointer to this instance's context
730 * \param[in] buf Buffer to store compressed data into
731 * \param[in] pad_before Bytes to skip before writing compressed data
732 * \param[in] pad_after Bytes to skip after writing compressed data
734 * \retval #VPX_CODEC_OK
735 * The buffer was set successfully.
736 * \retval #VPX_CODEC_INVALID_PARAM
737 * A parameter was NULL, the image format is unsupported, etc.
739 vpx_codec_err_t vpx_codec_set_cx_data_buf(vpx_codec_ctx_t *ctx,
740 const vpx_fixed_buf_t *buf,
741 unsigned int pad_before,
742 unsigned int pad_after);
745 /*!\brief Encoded data iterator
747 * Iterates over a list of data packets to be passed from the encoder to the
748 * application. The different kinds of packets available are enumerated in
749 * #vpx_codec_cx_pkt_kind.
751 * #VPX_CODEC_CX_FRAME_PKT packets should be passed to the application's
752 * muxer. Multiple compressed frames may be in the list.
753 * #VPX_CODEC_STATS_PKT packets should be appended to a global buffer.
755 * The application \ref MUST silently ignore any packet kinds that it does
756 * not recognize or support.
758 * The data buffers returned from this function are only guaranteed to be
759 * valid until the application makes another call to any vpx_codec_* function.
761 * \param[in] ctx Pointer to this instance's context
762 * \param[in,out] iter Iterator storage, initialized to NULL
764 * \return Returns a pointer to an output data packet (compressed frame data,
765 * two-pass statistics, etc.) or NULL to signal end-of-list.
768 const vpx_codec_cx_pkt_t *vpx_codec_get_cx_data(vpx_codec_ctx_t *ctx,
769 vpx_codec_iter_t *iter);
772 /*!\brief Get Preview Frame
774 * Returns an image that can be used as a preview. Shows the image as it would
775 * exist at the decompressor. The application \ref MUST NOT write into this
778 * \param[in] ctx Pointer to this instance's context
780 * \return Returns a pointer to a preview image, or NULL if no image is
784 const vpx_image_t *vpx_codec_get_preview_frame(vpx_codec_ctx_t *ctx);
787 /*!@} - end defgroup encoder*/