#include "wmv2dsp.h"
typedef struct IntraX8Context {
- VLC * j_ac_vlc[4];//they point to the static j_mb_vlc
- VLC * j_orient_vlc;
- VLC * j_dc_vlc[3];
+ VLC *j_ac_vlc[4]; // they point to the static j_mb_vlc
+ VLC *j_orient_vlc;
+ VLC *j_dc_vlc[3];
int use_quant_matrix;
-//set by ff_intrax8_common_init
- uint8_t * prediction_table;//2*(mb_w*2)
+
+ // set by ff_intrax8_common_init
+ uint8_t *prediction_table; // 2 * (mb_w * 2)
ScanTable scantable[3];
WMV2DSPContext wdsp;
uint8_t idct_permutation[64];
-//set by the caller codec
+
+ //set by the caller codec
MpegEncContext * s;
IntraX8DSPContext dsp;
int quant;
int dquant;
int qsum;
-//calculated per frame
+
+ // calculated per frame
int quant_dc_chroma;
int divide_quant_dc_luma;
int divide_quant_dc_chroma;
-//changed per block
+
+ // changed per block
int edges;
int flat_dc;
int predicted_dc;
int est_run;
} IntraX8Context;
-void ff_intrax8_common_init(IntraX8Context * w, MpegEncContext * const s);
-void ff_intrax8_common_end(IntraX8Context * w);
-int ff_intrax8_decode_picture(IntraX8Context * w, int quant, int halfpq);
+/**
+ * Initialize IntraX8 frame decoder.
+ * Requires valid MpegEncContext with valid s->mb_width before calling.
+ * @param w pointer to IntraX8Context
+ * @param s pointer to MpegEncContext of the parent codec
+ * @return 0 on success, a negative AVERROR value on error
+ */
+int ff_intrax8_common_init(IntraX8Context *w, MpegEncContext *const s);
+
+/**
+ * Destroy IntraX8 frame structure.
+ * @param w pointer to IntraX8Context
+ */
+void ff_intrax8_common_end(IntraX8Context *w);
+
+/**
+ * Decode single IntraX8 frame.
+ * The parent codec must fill s->loopfilter and s->gb (bitstream).
+ * The parent codec must call ff_mpv_frame_start() before calling this function.
+ * The parent codec must call ff_mpv_frame_end() after calling this function.
+ * This function does not use ff_mpv_decode_mb().
+ * lowres decoding is theoretically impossible.
+ * @param w pointer to IntraX8Context
+ * @param dquant doubled quantizer, it would be odd in case of VC-1 halfpq==1.
+ * @param quant_offset offset away from zero
+ */
+int ff_intrax8_decode_picture(IntraX8Context *w, int quant, int halfpq);
#endif /* AVCODEC_INTRAX8_H */