Diff: picojpeg/picojpeg.h

Revision:

0:c546b51ecf0b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/picojpeg/picojpeg.h	Tue Oct 11 01:24:18 2011 +0000
@@ -0,0 +1,102 @@
+//------------------------------------------------------------------------------
+// picojpeg v1.0 - Public domain, Rich Geldreich <richgel99@gmail.com>
+//------------------------------------------------------------------------------
+#ifndef PICOJPEG_H
+#define PICOJPEG_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Error codes
+enum
+{
+   PJPG_NO_MORE_BLOCKS = 1,
+   PJPG_BAD_DHT_COUNTS,
+   PJPG_BAD_DHT_INDEX,
+   PJPG_BAD_DHT_MARKER,
+   PJPG_BAD_DQT_MARKER,
+   PJPG_BAD_DQT_TABLE,
+   PJPG_BAD_PRECISION,
+   PJPG_BAD_HEIGHT,
+   PJPG_BAD_WIDTH,
+   PJPG_TOO_MANY_COMPONENTS,
+   PJPG_BAD_SOF_LENGTH,
+   PJPG_BAD_VARIABLE_MARKER,
+   PJPG_BAD_DRI_LENGTH,
+   PJPG_BAD_SOS_LENGTH,
+   PJPG_BAD_SOS_COMP_ID,
+   PJPG_W_EXTRA_BYTES_BEFORE_MARKER,
+   PJPG_NO_ARITHMITIC_SUPPORT,
+   PJPG_UNEXPECTED_MARKER,
+   PJPG_NOT_JPEG,
+   PJPG_UNSUPPORTED_MARKER,
+   PJPG_BAD_DQT_LENGTH,
+   PJPG_TOO_MANY_BLOCKS,
+   PJPG_UNDEFINED_QUANT_TABLE,
+   PJPG_UNDEFINED_HUFF_TABLE,
+   PJPG_NOT_SINGLE_SCAN,
+   PJPG_UNSUPPORTED_COLORSPACE,
+   PJPG_UNSUPPORTED_SAMP_FACTORS,
+   PJPG_DECODE_ERROR,
+   PJPG_BAD_RESTART_MARKER,
+   PJPG_ASSERTION_ERROR,
+   PJPG_BAD_SOS_SPECTRAL,
+   PJPG_BAD_SOS_SUCCESSIVE,
+   PJPG_STREAM_READ_ERROR,
+   PJPG_NOTENOUGHMEM,
+   PJPG_UNSUPPORTED_COMP_IDENT,
+   PJPG_UNSUPPORTED_QUANT_TABLE,
+   PJPG_UNSUPPORTED_MODE,
+};  
+
+// Scan types - currently only GRAYSCALE, YH1V1, and YH2V2 are actually supported.
+typedef enum
+{
+   PJPG_GRAYSCALE,
+   PJPG_YH1V1,
+   PJPG_YH2V1,
+   PJPG_YH1V2,
+   PJPG_YH2V2
+} pjpeg_scan_type_t;
+
+typedef struct
+{
+   // Image resolution
+   int m_width;
+   int m_height;
+   // Number of components (1 or 3)
+   int m_comps;
+   // Total number of minimum coded units (MCU's) per row/col.
+   int m_MCUSPerRow;
+   int m_MCUSPerCol;
+   // Scan type
+   pjpeg_scan_type_t m_scanType;
+   // MCU width/height in pixels
+   int m_MCUWidth;
+   int m_MCUHeight;
+   // Pointers to internal MCU pixel component buffers. 
+   // These buffers Will be filled with pixels each time pjpegDecodeMCU() is called successfully.
+   // Each MCU consists of (m_MCUWidth/8)*(m_MCUHeight/8) blocks (currently either 1 for greyscale/no subsampling, or 4 for H2V2 sampling factors), where each block is a contiguous array of 64 (8x8) bytes.
+   // For greyscale images, only the values in m_pMCUBufR are valid.
+   unsigned char *m_pMCUBufR;
+   unsigned char *m_pMCUBufG;
+   unsigned char *m_pMCUBufB;
+} pjpeg_image_info_t;
+
+typedef unsigned char (*pjpeg_need_bytes_callback_t)(unsigned char* pBuf, unsigned char buf_size, unsigned char *pBytes_actually_read, void *pCallback_data);
+
+// Initializes the decompressor. Returns 0 on success, or one of the above error codes on failure.
+// pNeed_bytes_callback will be called to fill the decompressor's internal input buffer.
+// Not thread safe.
+unsigned char pjpeg_decode_init(pjpeg_image_info_t *pInfo, pjpeg_need_bytes_callback_t pNeed_bytes_callback, void *pCallback_data);
+
+// Decompresses the file's next MCU. Returns 0 on success, PJPG_NO_MORE_BLOCKS if no more blocks are available, or an error code.
+// Must be called a total of m_MCUSPerRow*m_MCUSPerCol times to completely decompress the image.
+unsigned char pjpeg_decode_mcu(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // PICOJPEG_H