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Merged
seiya-git merged 1 commit into from
Dec 9, 2025
Merged

Copy video frame data to a new writable frame before ASS rendering #132

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7 changes: 5 additions & 2 deletions docs/CHANGELOG.md
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Original file line number Diff line number Diff line change
@@ -1,13 +1,16 @@
## Change log

### 0.36.0-dev.4 (20251205)
### 0.36.0-dev.x (20251209)
* Fix hinting
* Fix ass_set_storage_size not be called
* Switch submodule build system to meson
* Update avisynth(plus) headers to v12
* Update libass to 0.17.4
* Unicode-safe file reading
* Add frame size parameters
* Add set_default_storage_size boolean
* Use frame properties if they available for "YCbCr Matrix: None"
* Work with frame copy instead of just modifying it

### 0.35 (20210304)
* Windows MSVC: Update to libass v0.15
Expand All @@ -21,7 +24,7 @@
* Fix: possible crash on initializing phase (buffer overread, linux crashed, Windows was just lucky)

### 0.34 (20210301)
* Fix the fix: revert matrix change made in 0.33
* Fix the fix: revert matrix change made in 0.33
* Fix: Check matrix from .ASS file "YCbCr Matrix:" section besides "Video Colorspace:"
Recognized values are "tv.601" and "tv.709"

Expand Down
20 changes: 6 additions & 14 deletions src/assrender.c
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Expand Up @@ -57,13 +57,6 @@ static const char* detect_bom(const char* buf, const size_t bufsize) {
return "UTF-8";
}

#ifdef _WIN32
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#else
#include <sys/stat.h>
#endif

#ifdef _WIN32
static wchar_t *utf8_to_utf16le(const char *data) {
const int out_size = MultiByteToWideChar(CP_UTF8, 0, data, -1, NULL, 0);
Expand Down Expand Up @@ -216,7 +209,6 @@ AVS_Value AVSC_CC assrender_create(AVS_ScriptEnvironment* env, AVS_Value args,
AVS_FilterInfo* fi;
AVS_Clip* c = avs_new_c_filter(env, &fi, avs_array_elt(args, 0), 1);
const AVS_VideoInfo *vi = &fi->vi;
char e[250];

const char* f = avs_as_string(avs_array_elt(args, 1));
const char* vfr = avs_as_string(avs_array_elt(args, 2));
Expand Down Expand Up @@ -318,7 +310,7 @@ AVS_Value AVSC_CC assrender_create(AVS_ScriptEnvironment* env, AVS_Value args,
if (!strcasecmp(strrchr(f, '.'), ".srt")) {
FILE* fp = open_utf8_filename(f, "r");
if (!fp) {
sprintf(e, "AssRender: input file '%s' does not exist or is not a regular file", f);
const char* e = avs_sprintf(env, "AssRender: input file '%s' does not exist or is not a regular file", f);
v = avs_new_value_error(e);
avs_release_clip(c);
return v;
Expand All @@ -330,15 +322,15 @@ AVS_Value AVSC_CC assrender_create(AVS_ScriptEnvironment* env, AVS_Value args,

fp = open_utf8_filename(f, "rb");
if (!fp) {
sprintf(e, "AssRender: input file '%s' does not exist or is not a regular file", f);
const char* e = avs_sprintf(env, "AssRender: input file '%s' does not exist or is not a regular file", f);
v = avs_new_value_error(e);
avs_release_clip(c);
return v;
}

buf = read_file_bytes(fp, &bufsize);
if (!buf) {
sprintf(e, "AssRender: unable to read '%s'", f);
const char* e = avs_sprintf(env, "AssRender: unable to read '%s'", f);
v = avs_new_value_error(e);
avs_release_clip(c);
return v;
Expand All @@ -358,7 +350,7 @@ AVS_Value AVSC_CC assrender_create(AVS_ScriptEnvironment* env, AVS_Value args,
}

if (!ass) {
sprintf(e, "AssRender: unable to parse '%s'", f);
const char* e = avs_sprintf(env, "AssRender: unable to parse '%s'", f);
v = avs_new_value_error(e);
avs_release_clip(c);
return v;
Expand All @@ -371,7 +363,7 @@ AVS_Value AVSC_CC assrender_create(AVS_ScriptEnvironment* env, AVS_Value args,
FILE* fh = open_utf8_filename(vfr, "r");

if (!fh) {
sprintf(e, "AssRender: could not read timecodes file '%s'", vfr);
const char* e = avs_sprintf(env, "AssRender: could not read timecodes file '%s'", vfr);
v = avs_new_value_error(e);
avs_release_clip(c);
return v;
Expand All @@ -380,7 +372,7 @@ AVS_Value AVSC_CC assrender_create(AVS_ScriptEnvironment* env, AVS_Value args,
data->isvfr = 1;

if (fscanf(fh, "# timecode format v%d", &ver) != 1) {
sprintf(e, "AssRender: invalid timecodes file '%s'", vfr);
const char* e = avs_sprintf(env, "AssRender: invalid timecodes file '%s'", vfr);
v = avs_new_value_error(e);
avs_release_clip(c);
return v;
Expand Down
54 changes: 31 additions & 23 deletions src/assrender.h
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Expand Up @@ -9,42 +9,50 @@
#include <string.h>
#include <time.h>
#include <ass/ass.h>

#ifdef _WIN32
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
#else
# include <sys/stat.h>
#endif

#include "avs/config.h"
#ifdef AVS_WINDOWS
#include "avisynth_c.h"
# include "avisynth_c.h"
#else
#include <avisynth/avisynth_c.h>
# include <avisynth/avisynth_c.h>
#endif

#if defined(_MSC_VER)
#define __NO_ISOCEXT
#define __NO_INLINE__
# define __NO_ISOCEXT
# define __NO_INLINE__

#define strcasecmp _stricmp
#define atoll _atoi64
# define strcasecmp _stricmp
# define atoll _atoi64
#endif

typedef struct {
// premultiplied coefficients for integer scaled arithmetics
int y_r, y_g, y_b;
int u_r, u_g, u_b;
int v_r, v_g, v_b;
int offset_y;
bool valid;
// premultiplied coefficients for integer scaled arithmetics
int y_r, y_g, y_b;
int u_r, u_g, u_b;
int v_r, v_g, v_b;
int offset_y;
bool valid;
} ConversionMatrix;

typedef enum {
MATRIX_NONE = 0,
MATRIX_BT601,
MATRIX_PC601,
MATRIX_BT709,
MATRIX_PC709,
MATRIX_PC2020,
MATRIX_BT2020,
MATRIX_TVFCC,
MATRIX_PCFCC,
MATRIX_TV240M,
MATRIX_PC240M
MATRIX_NONE = 0,
MATRIX_BT601,
MATRIX_PC601,
MATRIX_BT709,
MATRIX_PC709,
MATRIX_PC2020,
MATRIX_BT2020,
MATRIX_TVFCC,
MATRIX_PCFCC,
MATRIX_TV240M,
MATRIX_PC240M
} matrix_type;

typedef void (* fPixel)(uint8_t** sub_img, uint8_t** data, uint32_t* pitch, uint32_t width, uint32_t height);
Expand Down
10 changes: 6 additions & 4 deletions src/include/avs/capi.h
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Expand Up @@ -42,10 +42,12 @@
#endif
#endif

#ifdef __cplusplus
# define EXTERN_C extern "C"
#else
# define EXTERN_C
#ifndef EXTERN_C
# ifdef __cplusplus
# define EXTERN_C extern "C"
# else
# define EXTERN_C
# endif
#endif

#ifdef AVS_WINDOWS
Expand Down
118 changes: 91 additions & 27 deletions src/render.c
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Expand Up @@ -893,58 +893,122 @@ AVS_VideoFrame* AVSC_CC assrender_get_frame(AVS_FilterInfo* p, int n)
udata* ud = (udata*)p->user_data;
ASS_Image* img;
AVS_VideoFrame* src;

AVS_VideoFrame* dst;
int64_t ts;
int changed;

// 1) Get upstream frame
src = avs_get_frame(p->child, n);

avs_make_writable(p->env, &src);
// 2) Allocate a new writable destination frame
dst = avs_new_video_frame_a(p->env, &p->vi, AVS_FRAME_ALIGN);
if (!dst) {
avs_release_video_frame(src);
return 0;
}

// 3) Copy src -> dst (real pixel copy), then free src

if (avs_is_planar(&p->vi)) {
if (avs_is_rgb(&p->vi)) {
// Planar RGB: R, G, B planes
const int planes[3] = { AVS_PLANAR_R, AVS_PLANAR_G, AVS_PLANAR_B };
for (int i = 0; i < 3; ++i) {
const uint8_t* srcp = avs_get_read_ptr_p(src, planes[i]);
int src_pitch = avs_get_pitch_p(src, planes[i]);
uint8_t* dstp = avs_get_write_ptr_p(dst, planes[i]);
int dst_pitch = avs_get_pitch_p(dst, planes[i]);
int row_size = avs_get_row_size_p(src, planes[i]);
int height = avs_get_height_p(src, planes[i]);
avs_bit_blt(p->env, dstp, dst_pitch, srcp, src_pitch, row_size, height);
}
}
else {
// Planar YUV: Y, U, V planes
const int planes[3] = { AVS_PLANAR_Y, AVS_PLANAR_U, AVS_PLANAR_V };
for (int i = 0; i < 3; ++i) {
const uint8_t* srcp = avs_get_read_ptr_p(src, planes[i]);
int src_pitch = avs_get_pitch_p(src, planes[i]);
uint8_t* dstp = avs_get_write_ptr_p(dst, planes[i]);
int dst_pitch = avs_get_pitch_p(dst, planes[i]);
int row_size = avs_get_row_size_p(src, planes[i]);
int height = avs_get_height_p(src, planes[i]);
avs_bit_blt(p->env, dstp, dst_pitch, srcp, src_pitch, row_size, height);
}
}
}
else {
// Packed formats (e.g. RGB32, YUY2, etc.)
const uint8_t* srcp = avs_get_read_ptr_p(src, AVS_DEFAULT_PLANE);
int src_pitch = avs_get_pitch_p(src, AVS_DEFAULT_PLANE);
uint8_t* dstp = avs_get_write_ptr_p(dst, AVS_DEFAULT_PLANE);
int dst_pitch = avs_get_pitch_p(dst, AVS_DEFAULT_PLANE);
int row_size = avs_get_row_size_p(src, AVS_DEFAULT_PLANE);
int height = avs_get_height_p(src, AVS_DEFAULT_PLANE);
avs_bit_blt(p->env, dstp, dst_pitch, srcp, src_pitch, row_size, height);
}

// Original frame no longer needed locally
avs_release_video_frame(src);

// 4) Compute timestamp for libass
if (!ud->isvfr) {
// it’s a casting party!
// it's a casting party!
ts = (int64_t)n * (int64_t)1000 * (int64_t)p->vi.fps_denominator / (int64_t)p->vi.fps_numerator;
} else {
}
else {
ts = ud->timestamp[n];
}

// 5) Render ASS
img = ass_render_frame(ud->ass_renderer, ud->ass, ts, &changed);

if (img) {
uint32_t height, width, pitch[2];
uint32_t width = p->vi.width;
uint32_t height = p->vi.height;
uint8_t* data[3];
uint32_t pitch[2];

// 6) Build write pointers for the copied frame (dst)
if (avs_is_planar(&p->vi) && !ud->greyscale) {
if (avs_is_rgb(&p->vi)) {
// planar RGB as 444
data[0] = avs_get_write_ptr_p(src, AVS_PLANAR_R);
data[1] = avs_get_write_ptr_p(src, AVS_PLANAR_G);
data[2] = avs_get_write_ptr_p(src, AVS_PLANAR_B);
pitch[0] = avs_get_pitch_p(src, AVS_DEFAULT_PLANE);
}
else {
data[0] = avs_get_write_ptr_p(src, AVS_PLANAR_Y);
data[1] = avs_get_write_ptr_p(src, AVS_PLANAR_U);
data[2] = avs_get_write_ptr_p(src, AVS_PLANAR_V);
pitch[0] = avs_get_pitch_p(src, AVS_PLANAR_Y);
pitch[1] = avs_get_pitch_p(src, AVS_PLANAR_U);
}
if (avs_is_rgb(&p->vi)) {
// planar RGB as 4:4:4
data[0] = avs_get_write_ptr_p(dst, AVS_PLANAR_R);
data[1] = avs_get_write_ptr_p(dst, AVS_PLANAR_G);
data[2] = avs_get_write_ptr_p(dst, AVS_PLANAR_B);
pitch[0] = avs_get_pitch_p(dst, AVS_DEFAULT_PLANE);
}
else {
data[0] = avs_get_write_ptr_p(dst, AVS_PLANAR_Y);
data[1] = avs_get_write_ptr_p(dst, AVS_PLANAR_U);
data[2] = avs_get_write_ptr_p(dst, AVS_PLANAR_V);
pitch[0] = avs_get_pitch_p(dst, AVS_PLANAR_Y);
pitch[1] = avs_get_pitch_p(dst, AVS_PLANAR_U);
}
}
else {
data[0] = avs_get_write_ptr_p(src, AVS_DEFAULT_PLANE);
pitch[0] = avs_get_pitch_p(src, AVS_DEFAULT_PLANE);
data[0] = avs_get_write_ptr_p(dst, AVS_DEFAULT_PLANE);
pitch[0] = avs_get_pitch_p(dst, AVS_DEFAULT_PLANE);
}

height = p->vi.height;
width = p->vi.width;

// 7) Rebuild cached subtitle bitmap if changed
if (changed) {
memset(ud->sub_img[0], 0x00, height * width * ud->pixelsize);
ud->f_make_sub_img(img, ud->sub_img, width, ud->bits_per_pixel, ud->rgb_fullscale, &ud->mx);
memset(ud->sub_img[0], 0, height * width * ud->pixelsize);
ud->f_make_sub_img(
img,
ud->sub_img,
width,
ud->bits_per_pixel,
ud->rgb_fullscale,
&ud->mx
);
}

// 8) Blend ASS into the copied frame
ud->apply(ud->sub_img, data, pitch, width, height);
}

return src;
// 9) Return the modified copy
return dst;
}