avcodec.h

     * the first is allways the native one
     * @return the choosen format
     * - encoding: unused
     * - decoding: set by user, if not set then the native format will always be choosen
     */
    enum PixelFormat (*get_format)(struct AVCodecContext *s, enum PixelFormat * fmt);

    /**
     * DTG active format information (additionnal aspect ratio
     * information only used in DVB MPEG2 transport streams). 0 if
     * not set.
     * 
     * - encoding: unused.
     * - decoding: set by decoder 
     */
    int dtg_active_format;
#define FF_DTG_AFD_SAME         8
#define FF_DTG_AFD_4_3          9
#define FF_DTG_AFD_16_9         10
#define FF_DTG_AFD_14_9         11
#define FF_DTG_AFD_4_3_SP_14_9  13
#define FF_DTG_AFD_16_9_SP_14_9 14
#define FF_DTG_AFD_SP_4_3       15

    int me_range;
    /**
     * Maximum motion estimation search range in subpel units.
     * if 0 then no limit
     * 
     * - encoding: set by user.
     * - decoding: unused.
     */

} AVCodecContext;


/**
 * AVOption.
 */
typedef struct AVOption {
    /** options' name */
    const char *name; /* if name is NULL, it indicates a link to next */
    /** short English text help or const struct AVOption* subpointer */
    const char *help; //	const struct AVOption* sub;
    /** offset to context structure where the parsed value should be stored */
    int offset;
    /** options' type */
    int type;
#define FF_OPT_TYPE_BOOL 1      ///< boolean - true,1,on  (or simply presence)
#define FF_OPT_TYPE_DOUBLE 2    ///< double
#define FF_OPT_TYPE_INT 3       ///< integer
#define FF_OPT_TYPE_STRING 4    ///< string (finished with \0)
#define FF_OPT_TYPE_MASK 0x1f	///< mask for types - upper bits are various flags
//#define FF_OPT_TYPE_EXPERT 0x20 // flag for expert option
#define FF_OPT_TYPE_FLAG (FF_OPT_TYPE_BOOL | 0x40)
#define FF_OPT_TYPE_RCOVERRIDE (FF_OPT_TYPE_STRING | 0x80)
    /** min value  (min == max   ->  no limits) */
    double min;
    /** maximum value for double/int */
    double max;
    /** default boo [0,1]l/double/int value */
    double defval;
    /**
     * default string value (with optional semicolon delimited extra option-list
     * i.e.   option1;option2;option3
     * defval might select other then first argument as default
     */
    const char *defstr;
#define FF_OPT_MAX_DEPTH 10
} AVOption;

/**
 * Parse option(s) and sets fields in passed structure
 * @param strct	structure where the parsed results will be written
 * @param list  list with AVOptions
 * @param opts	string with options for parsing
 */
int avoption_parse(void* strct, const AVOption* list, const char* opts);


/**
 * AVCodec.
 */
typedef struct AVCodec {
    const char *name;
    int type;
    int id;
    int priv_data_size;
    int (*init)(AVCodecContext *);
    int (*encode)(AVCodecContext *, uint8_t *buf, int buf_size, void *data);
    int (*close)(AVCodecContext *);
    int (*decode)(AVCodecContext *, void *outdata, int *outdata_size,
                  uint8_t *buf, int buf_size);
    int capabilities;
    const AVOption *options;
    struct AVCodec *next;
} AVCodec;

/**
 * four components are given, that's all.
 * the last component is alpha
 */
typedef struct AVPicture {
    uint8_t *data[4];
    int linesize[4];
} AVPicture;

extern AVCodec ac3_encoder;
extern AVCodec mp2_encoder;
extern AVCodec mp3lame_encoder;
extern AVCodec oggvorbis_encoder;
extern AVCodec mpeg1video_encoder;
extern AVCodec h263_encoder;
extern AVCodec h263p_encoder;
extern AVCodec rv10_encoder;
extern AVCodec mjpeg_encoder;
extern AVCodec mpeg4_encoder;
extern AVCodec msmpeg4v1_encoder;
extern AVCodec msmpeg4v2_encoder;
extern AVCodec msmpeg4v3_encoder;
extern AVCodec wmv1_encoder;
extern AVCodec wmv2_encoder;
extern AVCodec huffyuv_encoder;

extern AVCodec h263_decoder;
extern AVCodec mpeg4_decoder;
extern AVCodec msmpeg4v1_decoder;
extern AVCodec msmpeg4v2_decoder;
extern AVCodec msmpeg4v3_decoder;
extern AVCodec wmv1_decoder;
extern AVCodec wmv2_decoder;
extern AVCodec mpeg_decoder;
extern AVCodec h263i_decoder;
extern AVCodec rv10_decoder;
extern AVCodec svq1_decoder;
extern AVCodec dvvideo_decoder;
extern AVCodec dvaudio_decoder;
extern AVCodec wmav1_decoder;
extern AVCodec wmav2_decoder;
extern AVCodec mjpeg_decoder;
extern AVCodec mjpegb_decoder;
extern AVCodec mp2_decoder;
extern AVCodec mp3_decoder;
extern AVCodec mace3_decoder;
extern AVCodec mace6_decoder;
extern AVCodec huffyuv_decoder;
extern AVCodec oggvorbis_decoder;
extern AVCodec cyuv_decoder;

/* pcm codecs */
#define PCM_CODEC(id, name) \
extern AVCodec name ## _decoder; \
extern AVCodec name ## _encoder

PCM_CODEC(CODEC_ID_PCM_S16LE, pcm_s16le);
PCM_CODEC(CODEC_ID_PCM_S16BE, pcm_s16be);
PCM_CODEC(CODEC_ID_PCM_U16LE, pcm_u16le);
PCM_CODEC(CODEC_ID_PCM_U16BE, pcm_u16be);
PCM_CODEC(CODEC_ID_PCM_S8, pcm_s8);
PCM_CODEC(CODEC_ID_PCM_U8, pcm_u8);
PCM_CODEC(CODEC_ID_PCM_ALAW, pcm_alaw);
PCM_CODEC(CODEC_ID_PCM_MULAW, pcm_mulaw);

/* adpcm codecs */

PCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
PCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);
PCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);

#undef PCM_CODEC

/* dummy raw video codec */
extern AVCodec rawvideo_codec;

/* the following codecs use external GPL libs */
extern AVCodec ac3_decoder;

/* resample.c */

struct ReSampleContext;

typedef struct ReSampleContext ReSampleContext;

ReSampleContext *audio_resample_init(int output_channels, int input_channels, 
                                     int output_rate, int input_rate);
int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples);
void audio_resample_close(ReSampleContext *s);

/* YUV420 format is assumed ! */

struct ImgReSampleContext;

typedef struct ImgReSampleContext ImgReSampleContext;

ImgReSampleContext *img_resample_init(int output_width, int output_height,
                                      int input_width, int input_height);

ImgReSampleContext *img_resample_full_init(int owidth, int oheight,
                                      int iwidth, int iheight,
                                      int topBand, int bottomBand,
                                      int leftBand, int rightBand);

void img_resample(ImgReSampleContext *s, 
                  AVPicture *output, AVPicture *input);

void img_resample_close(ImgReSampleContext *s);

int avpicture_fill(AVPicture *picture, uint8_t *ptr,
                   int pix_fmt, int width, int height);
int avpicture_get_size(int pix_fmt, int width, int height);
void avcodec_get_chroma_sub_sample(int pix_fmt, int *h_shift, int *v_shift);
const char *avcodec_get_pix_fmt_name(int pix_fmt);

/* convert among pixel formats */
int img_convert(AVPicture *dst, int dst_pix_fmt,
                AVPicture *src, int pix_fmt, 
                int width, int height);

/* deinterlace a picture */
int avpicture_deinterlace(AVPicture *dst, AVPicture *src,
                          int pix_fmt, int width, int height);

/* external high level API */

extern AVCodec *first_avcodec;

/* returns LIBAVCODEC_VERSION_INT constant */
unsigned avcodec_version(void);
/* returns LIBAVCODEC_BUILD constant */
unsigned avcodec_build(void);
void avcodec_init(void);

void register_avcodec(AVCodec *format);
AVCodec *avcodec_find_encoder(enum CodecID id);
AVCodec *avcodec_find_encoder_by_name(const char *name);
AVCodec *avcodec_find_decoder(enum CodecID id);
AVCodec *avcodec_find_decoder_by_name(const char *name);
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);

void avcodec_get_context_defaults(AVCodecContext *s);
AVCodecContext *avcodec_alloc_context(void);
AVFrame *avcodec_alloc_frame(void);

int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);

int avcodec_open(AVCodecContext *avctx, AVCodec *codec);
int avcodec_decode_audio(AVCodecContext *avctx, int16_t *samples, 
                         int *frame_size_ptr,
                         uint8_t *buf, int buf_size);
int avcodec_decode_video(AVCodecContext *avctx, AVFrame *picture, 
                         int *got_picture_ptr,
                         uint8_t *buf, int buf_size);
int avcodec_parse_frame(AVCodecContext *avctx, uint8_t **pdata, 
                        int *data_size_ptr,
                        uint8_t *buf, int buf_size);
int avcodec_encode_audio(AVCodecContext *avctx, uint8_t *buf, int buf_size, 
                         const short *samples);
int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size, 
                         const AVFrame *pict);

int avcodec_close(AVCodecContext *avctx);

void avcodec_register_all(void);

void avcodec_flush_buffers(AVCodecContext *avctx);

/* misc usefull functions */
/**
 * reduce a fraction.
 * this is usefull for framerate calculations
 * @param max the maximum allowed for dst_nom & dst_den
 * @return 1 if exact, 0 otherwise
 */
int av_reduce(int *dst_nom, int *dst_den, int64_t nom, int64_t den, int64_t max);

/**
 * rescale a 64bit integer.
 * a simple a*b/c isnt possible as it can overflow
 */
int64_t av_rescale(int64_t a, int b, int c);


/**
 * Interface for 0.5.0 version
 *
 * do not even think about it's usage for this moment
 */

typedef struct {
    /// compressed size used from given memory buffer
    int size;
    /// I/P/B frame type
    int frame_type;
} avc_enc_result_t;

/**
 * Commands
 * order can't be changed - once it was defined
 */
typedef enum {
    // general commands
    AVC_OPEN_BY_NAME = 0xACA000,
    AVC_OPEN_BY_CODEC_ID,
    AVC_OPEN_BY_FOURCC,
    AVC_CLOSE,

    AVC_FLUSH,
    // pin - struct { uint8_t* src, uint_t src_size }
    // pout - struct { AVPicture* img, consumed_bytes,
    AVC_DECODE,
    // pin - struct { AVPicture* img, uint8_t* dest, uint_t dest_size }
    // pout - uint_t used_from_dest_size
    AVC_ENCODE, 

    // query/get video commands
    AVC_GET_VERSION = 0xACB000,
    AVC_GET_WIDTH,
    AVC_GET_HEIGHT,
    AVC_GET_DELAY,
    AVC_GET_QUANT_TABLE,
    // ...

    // query/get audio commands
    AVC_GET_FRAME_SIZE = 0xABC000,

    // maybe define some simple structure which
    // might be passed to the user - but they can't
    // contain any codec specific parts and these
    // calls are usualy necessary only few times

    // set video commands
    AVC_SET_WIDTH = 0xACD000,
    AVC_SET_HEIGHT,

    // set video encoding commands
    AVC_SET_FRAME_RATE = 0xACD800,
    AVC_SET_QUALITY,
    AVC_SET_HURRY_UP,

    // set audio commands
    AVC_SET_SAMPLE_RATE = 0xACE000,
    AVC_SET_CHANNELS,

} avc_cmd_t;

/**
 * \param handle  allocated private structure by libavcodec
 *                for initialization pass NULL - will be returned pout
 *                user is supposed to know nothing about its structure
 * \param cmd     type of operation to be performed
 * \param pint    input parameter
 * \param pout    output parameter
 *
 * \returns  command status - eventually for query command it might return
 * integer resulting value
 */
int avcodec(void* handle, avc_cmd_t cmd, void* pin, void* pout);

/* memory */
void *av_malloc(unsigned int size);
void *av_mallocz(unsigned int size);
void *av_realloc(void *ptr, unsigned int size);
void av_free(void *ptr);
char *av_strdup(const char *s);
void __av_freep(void **ptr);
#define av_freep(p) __av_freep((void **)(p))
void *av_fast_realloc(void *ptr, unsigned int *size, unsigned int min_size);
/* for static data only */
/* call av_free_static to release all staticaly allocated tables */
void av_free_static(void);
void *__av_mallocz_static(void** location, unsigned int size);
#define av_mallocz_static(p, s) __av_mallocz_static((void **)(p), s)

#ifdef __cplusplus
}
#endif

#endif /* AVCODEC_H */