* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
+#ifndef AVCODEC_PIXDESC_H
+#define AVCODEC_PIXDESC_H
+
#include <inttypes.h>
#include "libavutil/intreadwrite.h"
typedef struct AVComponentDescriptor{
uint16_t plane :2; ///< which of the 4 planes contains the component
- uint16_t step_minus1 :3; ///< number of bytes between 2 horizontally consecutive pixels minus 1
- uint16_t offset_plus1 :3; ///< number of bytes before the component of the first pixel plus 1
+
+ /**
+ * Number of elements between 2 horizontally consecutive pixels minus 1.
+ * Elements are bits for bitstream formats, bytes otherwise.
+ */
+ uint16_t step_minus1 :3;
+
+ /**
+ * Number of elements before the component of the first pixel plus 1.
+ * Elements are bits for bitstream formats, bytes otherwise.
+ */
+ uint16_t offset_plus1 :3;
uint16_t shift :3; ///< number of least significant bits that must be shifted away to get the value
uint16_t depth_minus1 :4; ///< number of bits in the component minus 1
}AVComponentDescriptor;
* are stored not what these values represent.
*/
typedef struct AVPixFmtDescriptor{
+ const char *name;
uint8_t nb_channels; ///< The number of components each pixel has, (1-4)
/**
#define PIX_FMT_PAL 2 ///< Pixel format has a palette in data[1], values are indexes in this palette.
#define PIX_FMT_BITSTREAM 4 ///< All values of a component are bit-wise packed end to end.
+/**
+ * The array of all the pixel format descriptors.
+ */
+extern const AVPixFmtDescriptor av_pix_fmt_descriptors[];
-static inline void read_line(uint16_t *dst, const uint8_t *data[4], const int linesize[4], AVPixFmtDescriptor *desc, int x, int y, int c, int w)
+/**
+ * Reads a line from an image, and writes to dst the values of the
+ * pixel format component c.
+ *
+ * @param data the array containing the pointers to the planes of the image
+ * @param linesizes the array containing the linesizes of the image
+ * @param desc the pixel format descriptor for the image
+ * @param x the horizontal coordinate of the first pixel to read
+ * @param y the vertical coordinate of the first pixel to read
+ * @param w the width of the line to read, that is the number of
+ * values to write to dst
+ * @param read_pal_component if not zero and the format is a paletted
+ * format writes to dst the values corresponding to the palette
+ * component c in data[1], rather than the palette indexes in
+ * data[0]. The behavior is undefined if the format is not paletted.
+ */
+static inline void read_line(uint16_t *dst, const uint8_t *data[4], const int linesize[4],
+ const AVPixFmtDescriptor *desc, int x, int y, int c, int w, int read_pal_component)
{
AVComponentDescriptor comp= desc->comp[c];
int plane= comp.plane;
int shift= comp.shift;
int step = comp.step_minus1+1;
int flags= desc->flags;
- const uint8_t *p= data[plane]+y*linesize[plane] + x * step + comp.offset_plus1 - 1;
-
- //FIXME initial x in case of PIX_FMT_BITSTREAM is wrong
-
- while(w--){
- int val;
- if(flags & PIX_FMT_BE) val= AV_RB16(p);
- else val= AV_RL16(p);
- val = (val>>shift) & mask;
- if(flags & PIX_FMT_PAL)
- val= data[1][4*val + c];
- if(flags & PIX_FMT_BITSTREAM){
- shift-=depth;
- while(shift<0){
- shift+=8;
- p++;
+
+ if (flags & PIX_FMT_BITSTREAM){
+ int skip = x*step + comp.offset_plus1-1;
+ const uint8_t *p = data[plane] + y*linesize[plane] + (skip>>3);
+ int shift = 8 - depth - (skip&7);
+
+ while(w--){
+ int val = (*p >> shift) & mask;
+ if(read_pal_component)
+ val= data[1][4*val + c];
+ shift -= step;
+ p -= shift>>3;
+ shift &= 7;
+ *dst++= val;
+ }
+ } else {
+ const uint8_t *p = data[plane]+ y*linesize[plane] + x*step + comp.offset_plus1-1;
+
+ while(w--){
+ int val;
+ if(flags & PIX_FMT_BE) val= AV_RB16(p);
+ else val= AV_RL16(p);
+ val = (val>>shift) & mask;
+ if(read_pal_component)
+ val= data[1][4*val + c];
+ p+= step;
+ *dst++= val;
+ }
+ }
+}
+
+/**
+ * Writes the values from src to the pixel format component c of an
+ * image line.
+ *
+ * @param src array containing the values to write
+ * @param data the array containing the pointers to the planes of the
+ * image to write into. It is supposed to be zeroed.
+ * @param linesizes the array containing the linesizes of the image
+ * @param desc the pixel format descriptor for the image
+ * @param x the horizontal coordinate of the first pixel to write
+ * @param y the vertical coordinate of the first pixel to write
+ * @param w the width of the line to write, that is the number of
+ * values to write to the image line
+ */
+static inline void write_line(const uint16_t *src, uint8_t *data[4], const int linesize[4],
+ const AVPixFmtDescriptor *desc, int x, int y, int c, int w)
+{
+ AVComponentDescriptor comp = desc->comp[c];
+ int plane = comp.plane;
+ int depth = comp.depth_minus1+1;
+ int step = comp.step_minus1+1;
+ int flags = desc->flags;
+
+ if (flags & PIX_FMT_BITSTREAM) {
+ int skip = x*step + comp.offset_plus1-1;
+ uint8_t *p = data[plane] + y*linesize[plane] + (skip>>3);
+ int shift = 8 - depth - (skip&7);
+
+ while (w--) {
+ *p |= *src++ << shift;
+ shift -= step;
+ p -= shift>>3;
+ shift &= 7;
+ }
+ } else {
+ int shift = comp.shift;
+ uint8_t *p = data[plane]+ y*linesize[plane] + x*step + comp.offset_plus1-1;
+
+ while (w--) {
+ if (flags & PIX_FMT_BE) {
+ uint16_t val = AV_RB16(p) | (*src++<<shift);
+ AV_WB16(p, val);
+ } else {
+ uint16_t val = AV_RL16(p) | (*src++<<shift);
+ AV_WL16(p, val);
}
- }else
p+= step;
- *dst++= val;
+ }
}
}
+
+/**
+ * Returns the number of bits per pixel used by the pixel format
+ * described by pixdesc.
+ *
+ * The returned number of bits refers to the number of bits actually
+ * used for storing the pixel information, that is padding bits are
+ * not counted.
+ */
+int av_get_bits_per_pixel(const AVPixFmtDescriptor *pixdesc);
+
+#endif /* AVCODEC_PIXDESC_H */