diff --git a/png.h b/png.h --- a/png.h +++ b/png.h @@ -329,8 +329,12 @@ */ # include "pnglibconf.h" #endif +#define PNG_APNG_SUPPORTED +#define PNG_READ_APNG_SUPPORTED +#define PNG_WRITE_APNG_SUPPORTED + #ifndef PNG_VERSION_INFO_ONLY /* Machine specific configuration. */ # include "pngconf.h" #endif @@ -424,8 +428,19 @@ extern "C" { * constants. * See pngconf.h for base types that vary by machine/system */ +#ifdef PNG_APNG_SUPPORTED +/* dispose_op flags from inside fcTL */ +#define PNG_DISPOSE_OP_NONE 0x00 +#define PNG_DISPOSE_OP_BACKGROUND 0x01 +#define PNG_DISPOSE_OP_PREVIOUS 0x02 + +/* blend_op flags from inside fcTL */ +#define PNG_BLEND_OP_SOURCE 0x00 +#define PNG_BLEND_OP_OVER 0x01 +#endif /* APNG */ + /* This triggers a compiler error in png.c, if png.c and png.h * do not agree upon the version number. */ typedef char* png_libpng_version_1_6_37; @@ -745,8 +760,12 @@ typedef png_unknown_chunk * * png_unknow #define PNG_INFO_sPLT 0x2000U /* ESR, 1.0.6 */ #define PNG_INFO_sCAL 0x4000U /* ESR, 1.0.6 */ #define PNG_INFO_IDAT 0x8000U /* ESR, 1.0.6 */ #define PNG_INFO_eXIf 0x10000U /* GR-P, 1.6.31 */ +#ifdef PNG_APNG_SUPPORTED +#define PNG_INFO_acTL 0x20000U +#define PNG_INFO_fcTL 0x40000U +#endif /* This is used for the transformation routines, as some of them * change these values for the row. It also should enable using * the routines for other purposes. @@ -782,8 +801,12 @@ typedef PNG_CALLBACK(void, *png_write_st #ifdef PNG_PROGRESSIVE_READ_SUPPORTED typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); +#ifdef PNG_APNG_SUPPORTED +typedef PNG_CALLBACK(void, *png_progressive_frame_ptr, (png_structp, + png_uint_32)); +#endif /* The following callback receives png_uint_32 row_number, int pass for the * png_bytep data of the row. When transforming an interlaced image the * row number is the row number within the sub-image of the interlace pass, so @@ -3226,17 +3249,90 @@ PNG_EXPORT(244, int, png_set_option, (pn /******************************************************************************* * END OF HARDWARE AND SOFTWARE OPTIONS ******************************************************************************/ +#ifdef PNG_APNG_SUPPORTED +PNG_EXPORT(248, png_uint_32, png_get_acTL, (png_structp png_ptr, + png_infop info_ptr, png_uint_32 *num_frames, png_uint_32 *num_plays)); + +PNG_EXPORT(249, png_uint_32, png_set_acTL, (png_structp png_ptr, + png_infop info_ptr, png_uint_32 num_frames, png_uint_32 num_plays)); + +PNG_EXPORT(250, png_uint_32, png_get_num_frames, (png_structp png_ptr, + png_infop info_ptr)); + +PNG_EXPORT(251, png_uint_32, png_get_num_plays, (png_structp png_ptr, + png_infop info_ptr)); + +PNG_EXPORT(252, png_uint_32, png_get_next_frame_fcTL, + (png_structp png_ptr, png_infop info_ptr, png_uint_32 *width, + png_uint_32 *height, png_uint_32 *x_offset, png_uint_32 *y_offset, + png_uint_16 *delay_num, png_uint_16 *delay_den, png_byte *dispose_op, + png_byte *blend_op)); + +PNG_EXPORT(253, png_uint_32, png_set_next_frame_fcTL, + (png_structp png_ptr, png_infop info_ptr, png_uint_32 width, + png_uint_32 height, png_uint_32 x_offset, png_uint_32 y_offset, + png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op, + png_byte blend_op)); + +PNG_EXPORT(254, png_uint_32, png_get_next_frame_width, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(255, png_uint_32, png_get_next_frame_height, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(256, png_uint_32, png_get_next_frame_x_offset, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(257, png_uint_32, png_get_next_frame_y_offset, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(258, png_uint_16, png_get_next_frame_delay_num, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(259, png_uint_16, png_get_next_frame_delay_den, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(260, png_byte, png_get_next_frame_dispose_op, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(261, png_byte, png_get_next_frame_blend_op, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(262, png_byte, png_get_first_frame_is_hidden, + (png_structp png_ptr, png_infop info_ptr)); +PNG_EXPORT(263, png_uint_32, png_set_first_frame_is_hidden, + (png_structp png_ptr, png_infop info_ptr, png_byte is_hidden)); + +#ifdef PNG_READ_APNG_SUPPORTED +PNG_EXPORT(264, void, png_read_frame_head, (png_structp png_ptr, + png_infop info_ptr)); +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +PNG_EXPORT(265, void, png_set_progressive_frame_fn, (png_structp png_ptr, + png_progressive_frame_ptr frame_info_fn, + png_progressive_frame_ptr frame_end_fn)); +#endif /* PROGRESSIVE_READ */ +#endif /* READ_APNG */ + +#ifdef PNG_WRITE_APNG_SUPPORTED +PNG_EXPORT(266, void, png_write_frame_head, (png_structp png_ptr, + png_infop info_ptr, png_bytepp row_pointers, + png_uint_32 width, png_uint_32 height, + png_uint_32 x_offset, png_uint_32 y_offset, + png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op, + png_byte blend_op)); + +PNG_EXPORT(267, void, png_write_frame_tail, (png_structp png_ptr, + png_infop info_ptr)); +#endif /* WRITE_APNG */ +#endif /* APNG */ + /* Maintainer: Put new public prototypes here ^, in libpng.3, in project * defs, and in scripts/symbols.def. */ /* The last ordinal number (this is the *last* one already used; the next * one to use is one more than this.) */ #ifdef PNG_EXPORT_LAST_ORDINAL +#ifdef PNG_APNG_SUPPORTED + PNG_EXPORT_LAST_ORDINAL(269); +#else PNG_EXPORT_LAST_ORDINAL(249); +#endif /* APNG */ #endif #ifdef __cplusplus } diff --git a/pngget.c b/pngget.c --- a/pngget.c +++ b/pngget.c @@ -1245,5 +1245,167 @@ png_get_palette_max(png_const_structp pn } # endif #endif +#ifdef PNG_APNG_SUPPORTED +png_uint_32 PNGAPI +png_get_acTL(png_structp png_ptr, png_infop info_ptr, + png_uint_32 *num_frames, png_uint_32 *num_plays) +{ + png_debug1(1, "in %s retrieval function", "acTL"); + + if (png_ptr != NULL && info_ptr != NULL && + (info_ptr->valid & PNG_INFO_acTL) != 0 && + num_frames != NULL && num_plays != NULL) + { + *num_frames = info_ptr->num_frames; + *num_plays = info_ptr->num_plays; + return (1); + } + + return (0); +} + +png_uint_32 PNGAPI +png_get_num_frames(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_num_frames()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->num_frames); + return (0); +} + +png_uint_32 PNGAPI +png_get_num_plays(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_num_plays()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->num_plays); + return (0); +} + +png_uint_32 PNGAPI +png_get_next_frame_fcTL(png_structp png_ptr, png_infop info_ptr, + png_uint_32 *width, png_uint_32 *height, + png_uint_32 *x_offset, png_uint_32 *y_offset, + png_uint_16 *delay_num, png_uint_16 *delay_den, + png_byte *dispose_op, png_byte *blend_op) +{ + png_debug1(1, "in %s retrieval function", "fcTL"); + + if (png_ptr != NULL && info_ptr != NULL && + (info_ptr->valid & PNG_INFO_fcTL) != 0 && + width != NULL && height != NULL && + x_offset != NULL && y_offset != NULL && + delay_num != NULL && delay_den != NULL && + dispose_op != NULL && blend_op != NULL) + { + *width = info_ptr->next_frame_width; + *height = info_ptr->next_frame_height; + *x_offset = info_ptr->next_frame_x_offset; + *y_offset = info_ptr->next_frame_y_offset; + *delay_num = info_ptr->next_frame_delay_num; + *delay_den = info_ptr->next_frame_delay_den; + *dispose_op = info_ptr->next_frame_dispose_op; + *blend_op = info_ptr->next_frame_blend_op; + return (1); + } + + return (0); +} + +png_uint_32 PNGAPI +png_get_next_frame_width(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_next_frame_width()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->next_frame_width); + return (0); +} + +png_uint_32 PNGAPI +png_get_next_frame_height(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_next_frame_height()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->next_frame_height); + return (0); +} + +png_uint_32 PNGAPI +png_get_next_frame_x_offset(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_next_frame_x_offset()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->next_frame_x_offset); + return (0); +} + +png_uint_32 PNGAPI +png_get_next_frame_y_offset(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_next_frame_y_offset()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->next_frame_y_offset); + return (0); +} + +png_uint_16 PNGAPI +png_get_next_frame_delay_num(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_next_frame_delay_num()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->next_frame_delay_num); + return (0); +} + +png_uint_16 PNGAPI +png_get_next_frame_delay_den(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_next_frame_delay_den()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->next_frame_delay_den); + return (0); +} + +png_byte PNGAPI +png_get_next_frame_dispose_op(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_next_frame_dispose_op()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->next_frame_dispose_op); + return (0); +} + +png_byte PNGAPI +png_get_next_frame_blend_op(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_get_next_frame_blend_op()"); + + if (png_ptr != NULL && info_ptr != NULL) + return (info_ptr->next_frame_blend_op); + return (0); +} + +png_byte PNGAPI +png_get_first_frame_is_hidden(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_first_frame_is_hidden()"); + + if (png_ptr != NULL) + return (png_byte)(png_ptr->apng_flags & PNG_FIRST_FRAME_HIDDEN); + + PNG_UNUSED(info_ptr) + + return 0; +} +#endif /* APNG */ #endif /* READ || WRITE */ diff --git a/pnginfo.h b/pnginfo.h --- a/pnginfo.h +++ b/pnginfo.h @@ -262,6 +262,19 @@ defined(PNG_READ_BACKGROUND_SUPPORTED) /* Data valid if (valid & PNG_INFO_IDAT) non-zero */ png_bytepp row_pointers; /* the image bits */ #endif +#ifdef PNG_APNG_SUPPORTED + png_uint_32 num_frames; /* including default image */ + png_uint_32 num_plays; + png_uint_32 next_frame_width; + png_uint_32 next_frame_height; + png_uint_32 next_frame_x_offset; + png_uint_32 next_frame_y_offset; + png_uint_16 next_frame_delay_num; + png_uint_16 next_frame_delay_den; + png_byte next_frame_dispose_op; + png_byte next_frame_blend_op; +#endif + }; #endif /* PNGINFO_H */ diff --git a/pngpread.c b/pngpread.c --- a/pngpread.c +++ b/pngpread.c @@ -194,8 +194,91 @@ png_push_read_chunk(png_structrp png_ptr } chunk_name = png_ptr->chunk_name; +#ifdef PNG_READ_APNG_SUPPORTED + if (png_ptr->num_frames_read > 0 && + png_ptr->num_frames_read < info_ptr->num_frames) + { + if (chunk_name == png_IDAT) + { + /* Discard trailing IDATs for the first frame */ + if ((png_ptr->mode & PNG_HAVE_fcTL) != 0 || + png_ptr->num_frames_read > 1) + png_error(png_ptr, "out of place IDAT"); + + PNG_PUSH_SAVE_BUFFER_IF_FULL + png_crc_finish(png_ptr, png_ptr->push_length); + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; + } + + else if (chunk_name == png_fdAT) + { + PNG_PUSH_SAVE_BUFFER_IF_LT(4) + png_ensure_sequence_number(png_ptr, 4); + + if ((png_ptr->mode & PNG_HAVE_fcTL) == 0) + { + /* Discard trailing fdATs for frames other than the first */ + if (png_ptr->num_frames_read < 2) + png_error(png_ptr, "out of place fdAT"); + + PNG_PUSH_SAVE_BUFFER_IF_FULL + png_crc_finish(png_ptr, png_ptr->push_length); + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; + } + + else + { + /* frame data follows */ + png_ptr->idat_size = png_ptr->push_length - 4; + png_ptr->mode |= PNG_HAVE_IDAT; + png_ptr->process_mode = PNG_READ_IDAT_MODE; + } + } + + else if (chunk_name == png_fcTL) + { + PNG_PUSH_SAVE_BUFFER_IF_FULL + png_read_reset(png_ptr); + png_ptr->mode &= ~PNG_HAVE_fcTL; + + png_handle_fcTL(png_ptr, info_ptr, png_ptr->push_length); + + if ((png_ptr->mode & PNG_HAVE_fcTL) == 0) + png_error(png_ptr, "missing required fcTL chunk"); + + png_read_reinit(png_ptr, info_ptr); + png_progressive_read_reset(png_ptr); + + if (png_ptr->frame_info_fn != NULL) + (*(png_ptr->frame_info_fn))(png_ptr, png_ptr->num_frames_read); + + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; + } + + else if (chunk_name == png_IEND) + { + PNG_PUSH_SAVE_BUFFER_IF_FULL + png_warning(png_ptr, "Number of actual frames fewer than expected"); + png_crc_finish(png_ptr, png_ptr->push_length); + png_ptr->process_mode = PNG_READ_DONE_MODE; + png_push_have_end(png_ptr, info_ptr); + } + + else + { + PNG_PUSH_SAVE_BUFFER_IF_FULL + png_warning(png_ptr, "Skipped (ignored) a chunk " + "between APNG chunks"); + png_crc_finish(png_ptr, png_ptr->push_length); + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; + } + + return; + } +#endif /* READ_APNG */ + if (chunk_name == png_IDAT) { if ((png_ptr->mode & PNG_AFTER_IDAT) != 0) png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; @@ -260,8 +343,11 @@ png_push_read_chunk(png_structrp png_ptr } else if (chunk_name == png_IDAT) { +#ifdef PNG_READ_APNG_SUPPORTED + png_have_info(png_ptr, info_ptr); +#endif png_ptr->idat_size = png_ptr->push_length; png_ptr->process_mode = PNG_READ_IDAT_MODE; png_push_have_info(png_ptr, info_ptr); png_ptr->zstream.avail_out = @@ -406,8 +492,22 @@ png_push_read_chunk(png_structrp png_ptr png_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length); } #endif +#ifdef PNG_READ_APNG_SUPPORTED + else if (chunk_name == png_acTL) + { + PNG_PUSH_SAVE_BUFFER_IF_FULL + png_handle_acTL(png_ptr, info_ptr, png_ptr->push_length); + } + + else if (chunk_name == png_fcTL) + { + PNG_PUSH_SAVE_BUFFER_IF_FULL + png_handle_fcTL(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif /* READ_APNG */ else { PNG_PUSH_SAVE_BUFFER_IF_FULL png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length, @@ -538,27 +638,74 @@ png_push_read_IDAT(png_structrp png_ptr) png_byte chunk_length[4]; png_byte chunk_tag[4]; /* TODO: this code can be commoned up with the same code in push_read */ +#ifdef PNG_READ_APNG_SUPPORTED + PNG_PUSH_SAVE_BUFFER_IF_LT(12) +#else PNG_PUSH_SAVE_BUFFER_IF_LT(8) +#endif png_push_fill_buffer(png_ptr, chunk_length, 4); png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length); png_reset_crc(png_ptr); png_crc_read(png_ptr, chunk_tag, 4); png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(chunk_tag); png_ptr->mode |= PNG_HAVE_CHUNK_HEADER; +#ifdef PNG_READ_APNG_SUPPORTED + if (png_ptr->chunk_name != png_fdAT && png_ptr->num_frames_read > 0) + { + if ((png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) != 0) + { + png_ptr->process_mode = PNG_READ_CHUNK_MODE; + if (png_ptr->frame_end_fn != NULL) + (*(png_ptr->frame_end_fn))(png_ptr, png_ptr->num_frames_read); + png_ptr->num_frames_read++; + return; + } + else + { + if (png_ptr->chunk_name == png_IEND) + png_error(png_ptr, "Not enough image data"); + PNG_PUSH_SAVE_BUFFER_IF_FULL + png_warning(png_ptr, "Skipping (ignoring) a chunk between " + "APNG chunks"); + png_crc_finish(png_ptr, png_ptr->push_length); + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; + return; + } + } + else +#endif +#ifdef PNG_READ_APNG_SUPPORTED + if (png_ptr->chunk_name != png_IDAT && png_ptr->num_frames_read == 0) +#else if (png_ptr->chunk_name != png_IDAT) +#endif { png_ptr->process_mode = PNG_READ_CHUNK_MODE; if ((png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0) png_error(png_ptr, "Not enough compressed data"); +#ifdef PNG_READ_APNG_SUPPORTED + if (png_ptr->frame_end_fn != NULL) + (*(png_ptr->frame_end_fn))(png_ptr, png_ptr->num_frames_read); + png_ptr->num_frames_read++; +#endif + return; } png_ptr->idat_size = png_ptr->push_length; + +#ifdef PNG_READ_APNG_SUPPORTED + if (png_ptr->num_frames_read > 0) + { + png_ensure_sequence_number(png_ptr, 4); + png_ptr->idat_size -= 4; + } +#endif } if (png_ptr->idat_size != 0 && png_ptr->save_buffer_size != 0) { @@ -630,8 +777,18 @@ png_process_IDAT_data(png_structrp png_p /* The caller checks for a non-zero buffer length. */ if (!(buffer_length > 0) || buffer == NULL) png_error(png_ptr, "No IDAT data (internal error)"); +#ifdef PNG_READ_APNG_SUPPORTED + /* If the app is not APNG-aware, decode only the first frame */ + if ((png_ptr->apng_flags & PNG_APNG_APP) == 0 && + png_ptr->num_frames_read > 0) + { + png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED; + return; + } +#endif + /* This routine must process all the data it has been given * before returning, calling the row callback as required to * handle the uncompressed results. */ @@ -1084,8 +1241,20 @@ png_set_progressive_read_fn(png_structrp png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer); } +#ifdef PNG_READ_APNG_SUPPORTED +void PNGAPI +png_set_progressive_frame_fn(png_structp png_ptr, + png_progressive_frame_ptr frame_info_fn, + png_progressive_frame_ptr frame_end_fn) +{ + png_ptr->frame_info_fn = frame_info_fn; + png_ptr->frame_end_fn = frame_end_fn; + png_ptr->apng_flags |= PNG_APNG_APP; +} +#endif + png_voidp PNGAPI png_get_progressive_ptr(png_const_structrp png_ptr) { if (png_ptr == NULL) diff --git a/pngpriv.h b/pngpriv.h --- a/pngpriv.h +++ b/pngpriv.h @@ -636,8 +636,12 @@ #define PNG_HAVE_PNG_SIGNATURE 0x1000U #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000U /* Have another chunk after IDAT */ /* 0x4000U (unused) */ #define PNG_IS_READ_STRUCT 0x8000U /* Else is a write struct */ +#ifdef PNG_APNG_SUPPORTED +#define PNG_HAVE_acTL 0x10000U +#define PNG_HAVE_fcTL 0x20000U +#endif /* Flags for the transformations the PNG library does on the image data */ #define PNG_BGR 0x0001U #define PNG_INTERLACE 0x0002U @@ -872,8 +876,18 @@ #define png_tIME PNG_U32(116, 73, 77, 69) #define png_tRNS PNG_U32(116, 82, 78, 83) #define png_zTXt PNG_U32(122, 84, 88, 116) +#ifdef PNG_APNG_SUPPORTED +#define png_acTL PNG_U32( 97, 99, 84, 76) +#define png_fcTL PNG_U32(102, 99, 84, 76) +#define png_fdAT PNG_U32(102, 100, 65, 84) + +/* For png_struct.apng_flags: */ +#define PNG_FIRST_FRAME_HIDDEN 0x0001U +#define PNG_APNG_APP 0x0002U +#endif + /* The following will work on (signed char*) strings, whereas the get_uint_32 * macro will fail on top-bit-set values because of the sign extension. */ #define PNG_CHUNK_FROM_STRING(s)\ @@ -1623,8 +1637,51 @@ PNG_INTERNAL_FUNCTION(void,png_push_read # endif #endif /* PROGRESSIVE_READ */ +#ifdef PNG_APNG_SUPPORTED +PNG_INTERNAL_FUNCTION(void,png_ensure_fcTL_is_valid,(png_structp png_ptr, + png_uint_32 width, png_uint_32 height, + png_uint_32 x_offset, png_uint_32 y_offset, + png_uint_16 delay_num, png_uint_16 delay_den, + png_byte dispose_op, png_byte blend_op),PNG_EMPTY); + +#ifdef PNG_READ_APNG_SUPPORTED +PNG_INTERNAL_FUNCTION(void,png_handle_acTL,(png_structp png_ptr, + png_infop info_ptr, png_uint_32 length),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_handle_fcTL,(png_structp png_ptr, + png_infop info_ptr, png_uint_32 length),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_handle_fdAT,(png_structp png_ptr, + png_infop info_ptr, png_uint_32 length),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_have_info,(png_structp png_ptr, + png_infop info_ptr),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_ensure_sequence_number,(png_structp png_ptr, + png_uint_32 length),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_read_reset,(png_structp png_ptr),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_read_reinit,(png_structp png_ptr, + png_infop info_ptr),PNG_EMPTY); +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +PNG_INTERNAL_FUNCTION(void,png_progressive_read_reset,(png_structp png_ptr), + PNG_EMPTY); +#endif /* PROGRESSIVE_READ */ +#endif /* READ_APNG */ + +#ifdef PNG_WRITE_APNG_SUPPORTED +PNG_INTERNAL_FUNCTION(void,png_write_acTL,(png_structp png_ptr, + png_uint_32 num_frames, png_uint_32 num_plays),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_write_fcTL,(png_structp png_ptr, + png_uint_32 width, png_uint_32 height, + png_uint_32 x_offset, png_uint_32 y_offset, + png_uint_16 delay_num, png_uint_16 delay_den, + png_byte dispose_op, png_byte blend_op),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_write_fdAT,(png_structp png_ptr, + png_const_bytep data, png_size_t length),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_write_reset,(png_structp png_ptr),PNG_EMPTY); +PNG_INTERNAL_FUNCTION(void,png_write_reinit,(png_structp png_ptr, + png_infop info_ptr, png_uint_32 width, png_uint_32 height),PNG_EMPTY); +#endif /* WRITE_APNG */ +#endif /* APNG */ + /* Added at libpng version 1.6.0 */ #ifdef PNG_GAMMA_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr, png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY); diff --git a/pngread.c b/pngread.c --- a/pngread.c +++ b/pngread.c @@ -160,8 +160,11 @@ png_read_info(png_structrp png_ptr, png_ png_handle_PLTE(png_ptr, info_ptr, length); else if (chunk_name == png_IDAT) { +#ifdef PNG_READ_APNG_SUPPORTED + png_have_info(png_ptr, info_ptr); +#endif png_ptr->idat_size = length; break; } @@ -254,15 +257,92 @@ png_read_info(png_structrp png_ptr, png_ else if (chunk_name == png_iTXt) png_handle_iTXt(png_ptr, info_ptr, length); #endif +#ifdef PNG_READ_APNG_SUPPORTED + else if (chunk_name == png_acTL) + png_handle_acTL(png_ptr, info_ptr, length); + + else if (chunk_name == png_fcTL) + png_handle_fcTL(png_ptr, info_ptr, length); + + else if (chunk_name == png_fdAT) + png_handle_fdAT(png_ptr, info_ptr, length); +#endif + else png_handle_unknown(png_ptr, info_ptr, length, PNG_HANDLE_CHUNK_AS_DEFAULT); } } #endif /* SEQUENTIAL_READ */ +#ifdef PNG_READ_APNG_SUPPORTED +void PNGAPI +png_read_frame_head(png_structp png_ptr, png_infop info_ptr) +{ + png_byte have_chunk_after_DAT; /* after IDAT or after fdAT */ + + png_debug(0, "Reading frame head"); + + if ((png_ptr->mode & PNG_HAVE_acTL) == 0) + png_error(png_ptr, "attempt to png_read_frame_head() but " + "no acTL present"); + + /* do nothing for the main IDAT */ + if (png_ptr->num_frames_read == 0) + return; + + png_read_reset(png_ptr); + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; + png_ptr->mode &= ~PNG_HAVE_fcTL; + + have_chunk_after_DAT = 0; + for (;;) + { + png_uint_32 length = png_read_chunk_header(png_ptr); + + if (png_ptr->chunk_name == png_IDAT) + { + /* discard trailing IDATs for the first frame */ + if (have_chunk_after_DAT != 0 || png_ptr->num_frames_read > 1) + png_error(png_ptr, "png_read_frame_head(): out of place IDAT"); + png_crc_finish(png_ptr, length); + } + + else if (png_ptr->chunk_name == png_fcTL) + { + png_handle_fcTL(png_ptr, info_ptr, length); + have_chunk_after_DAT = 1; + } + + else if (png_ptr->chunk_name == png_fdAT) + { + png_ensure_sequence_number(png_ptr, length); + + /* discard trailing fdATs for frames other than the first */ + if (have_chunk_after_DAT == 0 && png_ptr->num_frames_read > 1) + png_crc_finish(png_ptr, length - 4); + else if (png_ptr->mode & PNG_HAVE_fcTL) + { + png_ptr->idat_size = length - 4; + png_ptr->mode |= PNG_HAVE_IDAT; + + break; + } + else + png_error(png_ptr, "png_read_frame_head(): out of place fdAT"); + } + else + { + png_warning(png_ptr, "Skipped (ignored) a chunk " + "between APNG chunks"); + png_crc_finish(png_ptr, length); + } + } +} +#endif /* READ_APNG */ + /* Optional call to update the users info_ptr structure */ void PNGAPI png_read_update_info(png_structrp png_ptr, png_inforp info_ptr) { diff --git a/pngrutil.c b/pngrutil.c --- a/pngrutil.c +++ b/pngrutil.c @@ -864,8 +864,13 @@ png_handle_IHDR(png_structrp png_ptr, pn compression_type = buf[10]; filter_type = buf[11]; interlace_type = buf[12]; +#ifdef PNG_READ_APNG_SUPPORTED + png_ptr->first_frame_width = width; + png_ptr->first_frame_height = height; +#endif + /* Set internal variables */ png_ptr->width = width; png_ptr->height = height; png_ptr->bit_depth = (png_byte)bit_depth; @@ -2856,8 +2861,182 @@ png_handle_iTXt(png_structrp png_ptr, pn png_chunk_benign_error(png_ptr, errmsg); } #endif +#ifdef PNG_READ_APNG_SUPPORTED +void /* PRIVATE */ +png_handle_acTL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_byte data[8]; + png_uint_32 num_frames; + png_uint_32 num_plays; + png_uint_32 didSet; + + png_debug(1, "in png_handle_acTL"); + + if ((png_ptr->mode & PNG_HAVE_IHDR) == 0) + { + png_error(png_ptr, "Missing IHDR before acTL"); + } + else if ((png_ptr->mode & PNG_HAVE_IDAT) != 0) + { + png_warning(png_ptr, "Invalid acTL after IDAT skipped"); + png_crc_finish(png_ptr, length); + return; + } + else if ((png_ptr->mode & PNG_HAVE_acTL) != 0) + { + png_warning(png_ptr, "Duplicate acTL skipped"); + png_crc_finish(png_ptr, length); + return; + } + else if (length != 8) + { + png_warning(png_ptr, "acTL with invalid length skipped"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, data, 8); + png_crc_finish(png_ptr, 0); + + num_frames = png_get_uint_31(png_ptr, data); + num_plays = png_get_uint_31(png_ptr, data + 4); + + /* the set function will do error checking on num_frames */ + didSet = png_set_acTL(png_ptr, info_ptr, num_frames, num_plays); + if (didSet != 0) + png_ptr->mode |= PNG_HAVE_acTL; +} + +void /* PRIVATE */ +png_handle_fcTL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_byte data[22]; + png_uint_32 width; + png_uint_32 height; + png_uint_32 x_offset; + png_uint_32 y_offset; + png_uint_16 delay_num; + png_uint_16 delay_den; + png_byte dispose_op; + png_byte blend_op; + + png_debug(1, "in png_handle_fcTL"); + + png_ensure_sequence_number(png_ptr, length); + + if ((png_ptr->mode & PNG_HAVE_IHDR) == 0) + { + png_error(png_ptr, "Missing IHDR before fcTL"); + } + else if ((png_ptr->mode & PNG_HAVE_IDAT) != 0) + { + /* for any frames other then the first this message may be misleading, + * but correct. PNG_HAVE_IDAT is unset before the frame head is read + * i can't think of a better message */ + png_warning(png_ptr, "Invalid fcTL after IDAT skipped"); + png_crc_finish(png_ptr, length-4); + return; + } + else if ((png_ptr->mode & PNG_HAVE_fcTL) != 0) + { + png_warning(png_ptr, "Duplicate fcTL within one frame skipped"); + png_crc_finish(png_ptr, length-4); + return; + } + else if (length != 26) + { + png_warning(png_ptr, "fcTL with invalid length skipped"); + png_crc_finish(png_ptr, length-4); + return; + } + + png_crc_read(png_ptr, data, 22); + png_crc_finish(png_ptr, 0); + + width = png_get_uint_31(png_ptr, data); + height = png_get_uint_31(png_ptr, data + 4); + x_offset = png_get_uint_31(png_ptr, data + 8); + y_offset = png_get_uint_31(png_ptr, data + 12); + delay_num = png_get_uint_16(data + 16); + delay_den = png_get_uint_16(data + 18); + dispose_op = data[20]; + blend_op = data[21]; + + if (png_ptr->num_frames_read == 0 && (x_offset != 0 || y_offset != 0)) + { + png_warning(png_ptr, "fcTL for the first frame must have zero offset"); + return; + } + + if (info_ptr != NULL) + { + if (png_ptr->num_frames_read == 0 && + (width != info_ptr->width || height != info_ptr->height)) + { + png_warning(png_ptr, "size in first frame's fcTL must match " + "the size in IHDR"); + return; + } + + /* The set function will do more error checking */ + png_set_next_frame_fcTL(png_ptr, info_ptr, width, height, + x_offset, y_offset, delay_num, delay_den, + dispose_op, blend_op); + + png_read_reinit(png_ptr, info_ptr); + + png_ptr->mode |= PNG_HAVE_fcTL; + } +} + +void /* PRIVATE */ +png_have_info(png_structp png_ptr, png_infop info_ptr) +{ + if ((info_ptr->valid & PNG_INFO_acTL) != 0 && + (info_ptr->valid & PNG_INFO_fcTL) == 0) + { + png_ptr->apng_flags |= PNG_FIRST_FRAME_HIDDEN; + info_ptr->num_frames++; + } +} + +void /* PRIVATE */ +png_handle_fdAT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_ensure_sequence_number(png_ptr, length); + + /* This function is only called from png_read_end(), png_read_info(), + * and png_push_read_chunk() which means that: + * - the user doesn't want to read this frame + * - or this is an out-of-place fdAT + * in either case it is safe to ignore the chunk with a warning */ + png_warning(png_ptr, "ignoring fdAT chunk"); + png_crc_finish(png_ptr, length - 4); + PNG_UNUSED(info_ptr) +} + +void /* PRIVATE */ +png_ensure_sequence_number(png_structp png_ptr, png_uint_32 length) +{ + png_byte data[4]; + png_uint_32 sequence_number; + + if (length < 4) + png_error(png_ptr, "invalid fcTL or fdAT chunk found"); + + png_crc_read(png_ptr, data, 4); + sequence_number = png_get_uint_31(png_ptr, data); + + if (sequence_number != png_ptr->next_seq_num) + png_error(png_ptr, "fcTL or fdAT chunk with out-of-order sequence " + "number found"); + + png_ptr->next_seq_num++; +} +#endif /* READ_APNG */ + #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED /* Utility function for png_handle_unknown; set up png_ptr::unknown_chunk */ static int png_cache_unknown_chunk(png_structrp png_ptr, png_uint_32 length) @@ -3161,9 +3340,13 @@ png_check_chunk_length(png_const_structr # elif PNG_USER_CHUNK_MALLOC_MAX > 0 if (PNG_USER_CHUNK_MALLOC_MAX < limit) limit = PNG_USER_CHUNK_MALLOC_MAX; # endif +#ifdef PNG_READ_APNG_SUPPORTED + if (png_ptr->chunk_name == png_IDAT || png_ptr->chunk_name == png_fdAT) +#else if (png_ptr->chunk_name == png_IDAT) +#endif { png_alloc_size_t idat_limit = PNG_UINT_31_MAX; size_t row_factor = (size_t)png_ptr->width @@ -4165,8 +4348,40 @@ png_read_IDAT_data(png_structrp png_ptr, { uInt avail_in; png_bytep buffer; +#ifdef PNG_READ_APNG_SUPPORTED + png_uint_32 bytes_to_skip = 0; + + while (png_ptr->idat_size == 0 || bytes_to_skip != 0) + { + png_crc_finish(png_ptr, bytes_to_skip); + bytes_to_skip = 0; + + png_ptr->idat_size = png_read_chunk_header(png_ptr); + if (png_ptr->num_frames_read == 0) + { + if (png_ptr->chunk_name != png_IDAT) + png_error(png_ptr, "Not enough image data"); + } + else + { + if (png_ptr->chunk_name == png_IEND) + png_error(png_ptr, "Not enough image data"); + if (png_ptr->chunk_name != png_fdAT) + { + png_warning(png_ptr, "Skipped (ignored) a chunk " + "between APNG chunks"); + bytes_to_skip = png_ptr->idat_size; + continue; + } + + png_ensure_sequence_number(png_ptr, png_ptr->idat_size); + + png_ptr->idat_size -= 4; + } + } +#else while (png_ptr->idat_size == 0) { png_crc_finish(png_ptr, 0); @@ -4176,8 +4391,9 @@ png_read_IDAT_data(png_structrp png_ptr, */ if (png_ptr->chunk_name != png_IDAT) png_error(png_ptr, "Not enough image data"); } +#endif /* READ_APNG */ avail_in = png_ptr->IDAT_read_size; if (avail_in > png_ptr->idat_size) @@ -4239,8 +4455,11 @@ png_read_IDAT_data(png_structrp png_ptr, png_ptr->zstream.next_out = NULL; png_ptr->mode |= PNG_AFTER_IDAT; png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED; +#ifdef PNG_READ_APNG_SUPPORTED + png_ptr->num_frames_read++; +#endif if (png_ptr->zstream.avail_in > 0 || png_ptr->idat_size > 0) png_chunk_benign_error(png_ptr, "Extra compressed data"); break; @@ -4677,5 +4896,81 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED png_error(png_ptr, png_ptr->zstream.msg); png_ptr->flags |= PNG_FLAG_ROW_INIT; } + +#ifdef PNG_READ_APNG_SUPPORTED +/* This function is to be called after the main IDAT set has been read and + * before a new IDAT is read. It resets some parts of png_ptr + * to make them usable by the read functions again */ +void /* PRIVATE */ +png_read_reset(png_structp png_ptr) +{ + png_ptr->mode &= ~PNG_HAVE_IDAT; + png_ptr->mode &= ~PNG_AFTER_IDAT; + png_ptr->row_number = 0; + png_ptr->pass = 0; +} + +void /* PRIVATE */ +png_read_reinit(png_structp png_ptr, png_infop info_ptr) +{ + png_ptr->width = info_ptr->next_frame_width; + png_ptr->height = info_ptr->next_frame_height; + png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,png_ptr->width); + png_ptr->info_rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, + png_ptr->width); + if (png_ptr->prev_row != NULL) + memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1); +} + +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +/* same as png_read_reset() but for the progressive reader */ +void /* PRIVATE */ +png_progressive_read_reset(png_structp png_ptr) +{ +#ifdef PNG_READ_INTERLACING_SUPPORTED + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + + /* Start of interlace block */ + static PNG_CONST png_byte png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; + + /* Offset to next interlace block */ + static PNG_CONST png_byte png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; + + /* Start of interlace block in the y direction */ + static PNG_CONST png_byte png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1}; + + /* Offset to next interlace block in the y direction */ + static PNG_CONST png_byte png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2}; + + if (png_ptr->interlaced != 0) + { + if ((png_ptr->transformations & PNG_INTERLACE) == 0) + png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 - + png_pass_ystart[0]) / png_pass_yinc[0]; + else + png_ptr->num_rows = png_ptr->height; + + png_ptr->iwidth = (png_ptr->width + + png_pass_inc[png_ptr->pass] - 1 - + png_pass_start[png_ptr->pass]) / + png_pass_inc[png_ptr->pass]; + } + else +#endif /* READ_INTERLACING */ + { + png_ptr->num_rows = png_ptr->height; + png_ptr->iwidth = png_ptr->width; + } + png_ptr->flags &= ~PNG_FLAG_ZSTREAM_ENDED; + if (inflateReset(&(png_ptr->zstream)) != Z_OK) + png_error(png_ptr, "inflateReset failed"); + png_ptr->zstream.avail_in = 0; + png_ptr->zstream.next_in = 0; + png_ptr->zstream.next_out = png_ptr->row_buf; + png_ptr->zstream.avail_out = (uInt)PNG_ROWBYTES(png_ptr->pixel_depth, + png_ptr->iwidth) + 1; +} +#endif /* PROGRESSIVE_READ */ +#endif /* READ_APNG */ #endif /* READ */ diff --git a/pngset.c b/pngset.c --- a/pngset.c +++ b/pngset.c @@ -287,8 +287,13 @@ png_set_IHDR(png_const_structrp png_ptr, info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth); info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width); + +#ifdef PNG_APNG_SUPPORTED + /* for non-animated png. this may be overwritten from an acTL chunk later */ + info_ptr->num_frames = 1; +#endif } #ifdef PNG_oFFs_SUPPORTED void PNGAPI @@ -1157,8 +1162,148 @@ png_set_sPLT(png_const_structrp png_ptr, png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR); } #endif /* sPLT */ +#ifdef PNG_APNG_SUPPORTED +png_uint_32 PNGAPI +png_set_acTL(png_structp png_ptr, png_infop info_ptr, + png_uint_32 num_frames, png_uint_32 num_plays) +{ + png_debug1(1, "in %s storage function", "acTL"); + + if (png_ptr == NULL || info_ptr == NULL) + { + png_warning(png_ptr, + "Call to png_set_acTL() with NULL png_ptr " + "or info_ptr ignored"); + return (0); + } + if (num_frames == 0) + { + png_warning(png_ptr, + "Ignoring attempt to set acTL with num_frames zero"); + return (0); + } + if (num_frames > PNG_UINT_31_MAX) + { + png_warning(png_ptr, + "Ignoring attempt to set acTL with num_frames > 2^31-1"); + return (0); + } + if (num_plays > PNG_UINT_31_MAX) + { + png_warning(png_ptr, + "Ignoring attempt to set acTL with num_plays > 2^31-1"); + return (0); + } + + info_ptr->num_frames = num_frames; + info_ptr->num_plays = num_plays; + + info_ptr->valid |= PNG_INFO_acTL; + + return (1); +} + +/* delay_num and delay_den can hold any 16-bit values including zero */ +png_uint_32 PNGAPI +png_set_next_frame_fcTL(png_structp png_ptr, png_infop info_ptr, + png_uint_32 width, png_uint_32 height, + png_uint_32 x_offset, png_uint_32 y_offset, + png_uint_16 delay_num, png_uint_16 delay_den, + png_byte dispose_op, png_byte blend_op) +{ + png_debug1(1, "in %s storage function", "fcTL"); + + if (png_ptr == NULL || info_ptr == NULL) + { + png_warning(png_ptr, + "Call to png_set_fcTL() with NULL png_ptr or info_ptr " + "ignored"); + return (0); + } + + png_ensure_fcTL_is_valid(png_ptr, width, height, x_offset, y_offset, + delay_num, delay_den, dispose_op, blend_op); + + if (blend_op == PNG_BLEND_OP_OVER) + { + if ((png_ptr->color_type & PNG_COLOR_MASK_ALPHA) == 0 && + png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS) == 0) + { + png_warning(png_ptr, "PNG_BLEND_OP_OVER is meaningless " + "and wasteful for opaque images, ignored"); + blend_op = PNG_BLEND_OP_SOURCE; + } + } + + info_ptr->next_frame_width = width; + info_ptr->next_frame_height = height; + info_ptr->next_frame_x_offset = x_offset; + info_ptr->next_frame_y_offset = y_offset; + info_ptr->next_frame_delay_num = delay_num; + info_ptr->next_frame_delay_den = delay_den; + info_ptr->next_frame_dispose_op = dispose_op; + info_ptr->next_frame_blend_op = blend_op; + + info_ptr->valid |= PNG_INFO_fcTL; + + return (1); +} + +void /* PRIVATE */ +png_ensure_fcTL_is_valid(png_structp png_ptr, + png_uint_32 width, png_uint_32 height, + png_uint_32 x_offset, png_uint_32 y_offset, + png_uint_16 delay_num, png_uint_16 delay_den, + png_byte dispose_op, png_byte blend_op) +{ + if (width == 0 || width > PNG_UINT_31_MAX) + png_error(png_ptr, "invalid width in fcTL (0 or > 2^31-1)"); + if (height == 0 || height > PNG_UINT_31_MAX) + png_error(png_ptr, "invalid height in fcTL (0 or > 2^31-1)"); + if (x_offset > PNG_UINT_31_MAX) + png_error(png_ptr, "invalid x_offset in fcTL (> 2^31-1)"); + if (y_offset > PNG_UINT_31_MAX) + png_error(png_ptr, "invalid y_offset in fcTL (> 2^31-1)"); + if (width + x_offset > png_ptr->first_frame_width || + height + y_offset > png_ptr->first_frame_height) + png_error(png_ptr, "dimensions of a frame are greater than " + "the ones in IHDR"); + + if (dispose_op != PNG_DISPOSE_OP_NONE && + dispose_op != PNG_DISPOSE_OP_BACKGROUND && + dispose_op != PNG_DISPOSE_OP_PREVIOUS) + png_error(png_ptr, "invalid dispose_op in fcTL"); + + if (blend_op != PNG_BLEND_OP_SOURCE && + blend_op != PNG_BLEND_OP_OVER) + png_error(png_ptr, "invalid blend_op in fcTL"); + + PNG_UNUSED(delay_num) + PNG_UNUSED(delay_den) +} + +png_uint_32 PNGAPI +png_set_first_frame_is_hidden(png_structp png_ptr, png_infop info_ptr, + png_byte is_hidden) +{ + png_debug(1, "in png_first_frame_is_hidden()"); + + if (png_ptr == NULL) + return 0; + + if (is_hidden != 0) + png_ptr->apng_flags |= PNG_FIRST_FRAME_HIDDEN; + else + png_ptr->apng_flags &= ~PNG_FIRST_FRAME_HIDDEN; + + PNG_UNUSED(info_ptr) + + return 1; +} +#endif /* APNG */ + #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED static png_byte check_location(png_const_structrp png_ptr, int location) { diff --git a/pngstruct.h b/pngstruct.h --- a/pngstruct.h +++ b/pngstruct.h @@ -408,8 +408,29 @@ struct png_struct_def #ifdef PNG_MNG_FEATURES_SUPPORTED png_byte filter_type; #endif +#ifdef PNG_APNG_SUPPORTED + png_uint_32 apng_flags; + png_uint_32 next_seq_num; /* next fcTL/fdAT chunk sequence number */ + png_uint_32 first_frame_width; + png_uint_32 first_frame_height; + +#ifdef PNG_READ_APNG_SUPPORTED + png_uint_32 num_frames_read; /* incremented after all image data of */ + /* a frame is read */ +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED + png_progressive_frame_ptr frame_info_fn; /* frame info read callback */ + png_progressive_frame_ptr frame_end_fn; /* frame data read callback */ +#endif +#endif + +#ifdef PNG_WRITE_APNG_SUPPORTED + png_uint_32 num_frames_to_write; + png_uint_32 num_frames_written; +#endif +#endif /* APNG */ + /* New members added in libpng-1.2.0 */ /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */ #ifdef PNG_USER_MEM_SUPPORTED diff --git a/pngwrite.c b/pngwrite.c --- a/pngwrite.c +++ b/pngwrite.c @@ -127,8 +127,12 @@ png_write_info_before_PLTE(png_structrp * an error and calls png_error while the color space is being set, yet * the application continues writing the PNG. So check the 'invalid' * flag here too. */ +#ifdef PNG_WRITE_APNG_SUPPORTED + if ((info_ptr->valid & PNG_INFO_acTL) != 0) + png_write_acTL(png_ptr, info_ptr->num_frames, info_ptr->num_plays); +#endif #ifdef PNG_GAMMA_SUPPORTED # ifdef PNG_WRITE_gAMA_SUPPORTED if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 && (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_gAMA) != 0 && @@ -364,8 +368,13 @@ png_write_end(png_structrp png_ptr, png_ if ((png_ptr->mode & PNG_HAVE_IDAT) == 0) png_error(png_ptr, "No IDATs written into file"); +#ifdef PNG_WRITE_APNG_SUPPORTED + if (png_ptr->num_frames_written != png_ptr->num_frames_to_write) + png_error(png_ptr, "Not enough frames written"); +#endif + #ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED if (png_ptr->num_palette_max > png_ptr->num_palette) png_benign_error(png_ptr, "Wrote palette index exceeding num_palette"); #endif @@ -2391,5 +2400,43 @@ png_image_write_to_file(png_imagep image return 0; } #endif /* SIMPLIFIED_WRITE_STDIO */ #endif /* SIMPLIFIED_WRITE */ + +#ifdef PNG_WRITE_APNG_SUPPORTED +void PNGAPI +png_write_frame_head(png_structp png_ptr, png_infop info_ptr, + png_bytepp row_pointers, png_uint_32 width, png_uint_32 height, + png_uint_32 x_offset, png_uint_32 y_offset, + png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op, + png_byte blend_op) +{ + png_debug(1, "in png_write_frame_head"); + + /* there is a chance this has been set after png_write_info was called, + * so it would be set but not written. is there a way to be sure? */ + if ((info_ptr->valid & PNG_INFO_acTL) == 0) + png_error(png_ptr, "png_write_frame_head(): acTL not set"); + + png_write_reset(png_ptr); + + png_write_reinit(png_ptr, info_ptr, width, height); + + if ((png_ptr->apng_flags & PNG_FIRST_FRAME_HIDDEN) == 0 || + png_ptr->num_frames_written != 0) + png_write_fcTL(png_ptr, width, height, x_offset, y_offset, + delay_num, delay_den, dispose_op, blend_op); + + PNG_UNUSED(row_pointers) +} + +void PNGAPI +png_write_frame_tail(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_write_frame_tail"); + + png_ptr->num_frames_written++; + + PNG_UNUSED(info_ptr) +} +#endif /* WRITE_APNG */ #endif /* WRITE */ diff --git a/pngwutil.c b/pngwutil.c --- a/pngwutil.c +++ b/pngwutil.c @@ -820,8 +820,13 @@ png_write_IHDR(png_structrp png_ptr, png /* Write the chunk */ png_write_complete_chunk(png_ptr, png_IHDR, buf, 13); +#ifdef PNG_WRITE_APNG_SUPPORTED + png_ptr->first_frame_width = width; + png_ptr->first_frame_height = height; +#endif + if ((png_ptr->do_filter) == PNG_NO_FILTERS) { if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE || png_ptr->bit_depth < 8) @@ -1002,9 +1007,19 @@ png_compress_IDAT(png_structrp png_ptr, optimize_cmf(data, png_image_size(png_ptr)); #endif if (size > 0) +#ifdef PNG_WRITE_APNG_SUPPORTED + { + if (png_ptr->num_frames_written == 0) +#endif png_write_complete_chunk(png_ptr, png_IDAT, data, size); +#ifdef PNG_WRITE_APNG_SUPPORTED + else + png_write_fdAT(png_ptr, data, size); + } +#endif /* WRITE_APNG */ + png_ptr->mode |= PNG_HAVE_IDAT; png_ptr->zstream.next_out = data; png_ptr->zstream.avail_out = size; @@ -1049,9 +1064,19 @@ png_compress_IDAT(png_structrp png_ptr, optimize_cmf(data, png_image_size(png_ptr)); #endif if (size > 0) +#ifdef PNG_WRITE_APNG_SUPPORTED + { + if (png_ptr->num_frames_written == 0) +#endif png_write_complete_chunk(png_ptr, png_IDAT, data, size); +#ifdef PNG_WRITE_APNG_SUPPORTED + else + png_write_fdAT(png_ptr, data, size); + } +#endif /* WRITE_APNG */ + png_ptr->zstream.avail_out = 0; png_ptr->zstream.next_out = NULL; png_ptr->mode |= PNG_HAVE_IDAT | PNG_AFTER_IDAT; @@ -1884,8 +1909,84 @@ png_write_tIME(png_structrp png_ptr, png png_write_complete_chunk(png_ptr, png_tIME, buf, 7); } #endif +#ifdef PNG_WRITE_APNG_SUPPORTED +void /* PRIVATE */ +png_write_acTL(png_structp png_ptr, + png_uint_32 num_frames, png_uint_32 num_plays) +{ + png_byte buf[8]; + + png_debug(1, "in png_write_acTL"); + + png_ptr->num_frames_to_write = num_frames; + + if ((png_ptr->apng_flags & PNG_FIRST_FRAME_HIDDEN) != 0) + num_frames--; + + png_save_uint_32(buf, num_frames); + png_save_uint_32(buf + 4, num_plays); + + png_write_complete_chunk(png_ptr, png_acTL, buf, (png_size_t)8); +} + +void /* PRIVATE */ +png_write_fcTL(png_structp png_ptr, png_uint_32 width, png_uint_32 height, + png_uint_32 x_offset, png_uint_32 y_offset, + png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op, + png_byte blend_op) +{ + png_byte buf[26]; + + png_debug(1, "in png_write_fcTL"); + + if (png_ptr->num_frames_written == 0 && (x_offset != 0 || y_offset != 0)) + png_error(png_ptr, "x and/or y offset for the first frame aren't 0"); + if (png_ptr->num_frames_written == 0 && + (width != png_ptr->first_frame_width || + height != png_ptr->first_frame_height)) + png_error(png_ptr, "width and/or height in the first frame's fcTL " + "don't match the ones in IHDR"); + + /* more error checking */ + png_ensure_fcTL_is_valid(png_ptr, width, height, x_offset, y_offset, + delay_num, delay_den, dispose_op, blend_op); + + png_save_uint_32(buf, png_ptr->next_seq_num); + png_save_uint_32(buf + 4, width); + png_save_uint_32(buf + 8, height); + png_save_uint_32(buf + 12, x_offset); + png_save_uint_32(buf + 16, y_offset); + png_save_uint_16(buf + 20, delay_num); + png_save_uint_16(buf + 22, delay_den); + buf[24] = dispose_op; + buf[25] = blend_op; + + png_write_complete_chunk(png_ptr, png_fcTL, buf, (png_size_t)26); + + png_ptr->next_seq_num++; +} + +void /* PRIVATE */ +png_write_fdAT(png_structp png_ptr, + png_const_bytep data, png_size_t length) +{ + png_byte buf[4]; + + png_write_chunk_header(png_ptr, png_fdAT, (png_uint_32)(4 + length)); + + png_save_uint_32(buf, png_ptr->next_seq_num); + png_write_chunk_data(png_ptr, buf, 4); + + png_write_chunk_data(png_ptr, data, length); + + png_write_chunk_end(png_ptr); + + png_ptr->next_seq_num++; +} +#endif /* WRITE_APNG */ + /* Initializes the row writing capability of libpng */ void /* PRIVATE */ png_write_start_row(png_structrp png_ptr) { @@ -2777,5 +2878,40 @@ png_write_filtered_row(png_structrp png_ png_write_flush(png_ptr); } #endif /* WRITE_FLUSH */ } + +#ifdef PNG_WRITE_APNG_SUPPORTED +void /* PRIVATE */ +png_write_reset(png_structp png_ptr) +{ + png_ptr->row_number = 0; + png_ptr->pass = 0; + png_ptr->mode &= ~PNG_HAVE_IDAT; +} + +void /* PRIVATE */ +png_write_reinit(png_structp png_ptr, png_infop info_ptr, + png_uint_32 width, png_uint_32 height) +{ + if (png_ptr->num_frames_written == 0 && + (width != png_ptr->first_frame_width || + height != png_ptr->first_frame_height)) + png_error(png_ptr, "width and/or height in the first frame's fcTL " + "don't match the ones in IHDR"); + if (width > png_ptr->first_frame_width || + height > png_ptr->first_frame_height) + png_error(png_ptr, "width and/or height for a frame greater than " + "the ones in IHDR"); + + png_set_IHDR(png_ptr, info_ptr, width, height, + info_ptr->bit_depth, info_ptr->color_type, + info_ptr->interlace_type, info_ptr->compression_type, + info_ptr->filter_type); + + png_ptr->width = width; + png_ptr->height = height; + png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width); + png_ptr->usr_width = png_ptr->width; +} +#endif /* WRITE_APNG */ #endif /* WRITE */