Add ability to handle multiple palettes and objects simultaneously.
Each simultaneous object is given its own AVSubtitleRect.
Note that there can be up to 64 currently valid objects, but only
2 at any one time can be "presented".
---
libavcodec/pgssubdec.c | 352 +++++++++++++++++++++++++++++++++++--------------
1 file changed, 252 insertions(+), 100 deletions(-)
diff --git a/libavcodec/pgssubdec.c b/libavcodec/pgssubdec.c
index 4f175a3..ffb0f72 100644
--- a/libavcodec/pgssubdec.c
+++ b/libavcodec/pgssubdec.c
@@ -33,38 +33,107 @@
#include "libavutil/imgutils.h"
#define RGBA(r,g,b,a) (((a) << 24) | ((r) << 16) | ((g) << 8) | (b))
+#define MAX_EPOCH_PALETTES 8 // Max 8 allowed per PGS epoch
+#define MAX_EPOCH_OBJECTS 64 // Max 64 allowed per PGS epoch
+#define MAX_OBJECT_REFS 2 // Max objects per display set
enum SegmentType {
PALETTE_SEGMENT = 0x14,
- PICTURE_SEGMENT = 0x15,
+ OBJECT_SEGMENT = 0x15,
PRESENTATION_SEGMENT = 0x16,
WINDOW_SEGMENT = 0x17,
DISPLAY_SEGMENT = 0x80,
};
+typedef struct PGSSubObjectRef {
+ int id;
+ int window_id;
+ uint8_t composition_flag;
+ int x;
+ int y;
+ int crop_x;
+ int crop_y;
+ int crop_w;
+ int crop_h;
+} PGSSubObjectRef;
+
typedef struct PGSSubPresentation {
- int x;
- int y;
int id_number;
- int object_number;
- uint8_t composition_flag;
+ int palette_id;
+ int object_count;
+ PGSSubObjectRef objects[MAX_OBJECT_REFS];
int64_t pts;
} PGSSubPresentation;
-typedef struct PGSSubPicture {
+typedef struct PGSSubObject {
+ int id;
int w;
int h;
uint8_t *rle;
unsigned int rle_buffer_size, rle_data_len;
unsigned int rle_remaining_len;
-} PGSSubPicture;
+} PGSSubObject;
+
+typedef struct PGSSubObjects {
+ int count;
+ PGSSubObject object[MAX_EPOCH_OBJECTS];
+} PGSSubObjects;
+
+typedef struct PGSSubPalette {
+ int id;
+ uint32_t clut[256];
+} PGSSubPalette;
+
+typedef struct PGSSubPalettes {
+ int count;
+ PGSSubPalette palette[MAX_EPOCH_PALETTES];
+} PGSSubPalettes;
typedef struct PGSSubContext {
PGSSubPresentation presentation;
- uint32_t clut[256];
- PGSSubPicture picture;
+ PGSSubPalettes palettes;
+ PGSSubObjects objects;
} PGSSubContext;
+static void close_objects(PGSSubObjects *objects)
+{
+ int i;
+
+ for (i = 0; i < objects->count; i++) {
+ av_freep(&objects->object[i].rle);
+ objects->object[i].rle_buffer_size = 0;
+ objects->object[i].rle_remaining_len = 0;
+ }
+ objects->count = 0;
+}
+
+static void close_palettes(PGSSubPalettes *palettes)
+{
+ palettes->count = 0;
+}
+
+static PGSSubObject * find_object(int id, PGSSubObjects *objects)
+{
+ int i;
+
+ for (i = 0; i < objects->count; i++) {
+ if (objects->object[i].id == id)
+ return &objects->object[i];
+ }
+ return NULL;
+}
+
+static PGSSubPalette * find_palette(int id, PGSSubPalettes *palettes)
+{
+ int i;
+
+ for (i = 0; i < palettes->count; i++) {
+ if (palettes->palette[i].id == id)
+ return &palettes->palette[i];
+ }
+ return NULL;
+}
+
static av_cold int init_decoder(AVCodecContext *avctx)
{
avctx->pix_fmt = AV_PIX_FMT_PAL8;
@@ -76,8 +145,8 @@ static av_cold int close_decoder(AVCodecContext *avctx)
{
PGSSubContext *ctx = avctx->priv_data;
- av_freep(&ctx->picture.rle);
- ctx->picture.rle_buffer_size = 0;
+ close_objects(&ctx->objects);
+ close_palettes(&ctx->palettes);
return 0;
}
@@ -92,7 +161,7 @@ static av_cold int close_decoder(AVCodecContext *avctx)
* @param buf pointer to the RLE data to process
* @param buf_size size of the RLE data to process
*/
-static int decode_rle(AVCodecContext *avctx, AVSubtitle *sub,
+static int decode_rle(AVCodecContext *avctx, AVSubtitleRect *rect,
const uint8_t *buf, unsigned int buf_size)
{
const uint8_t *rle_bitmap_end;
@@ -100,15 +169,15 @@ static int decode_rle(AVCodecContext *avctx, AVSubtitle
*sub,
rle_bitmap_end = buf + buf_size;
- sub->rects[0]->pict.data[0] = av_malloc(sub->rects[0]->w *
sub->rects[0]->h);
+ rect->pict.data[0] = av_malloc(rect->w * rect->h);
- if (!sub->rects[0]->pict.data[0])
+ if (!rect->pict.data[0])
return -1;
pixel_count = 0;
line_count = 0;
- while (buf < rle_bitmap_end && line_count < sub->rects[0]->h) {
+ while (buf < rle_bitmap_end && line_count < rect->h) {
uint8_t flags, color;
int run;
@@ -123,27 +192,27 @@ static int decode_rle(AVCodecContext *avctx, AVSubtitle
*sub,
color = flags & 0x80 ? bytestream_get_byte(&buf) : 0;
}
- if (run > 0 && pixel_count + run <= sub->rects[0]->w *
sub->rects[0]->h) {
- memset(sub->rects[0]->pict.data[0] + pixel_count, color, run);
+ if (run > 0 && pixel_count + run <= rect->w * rect->h) {
+ memset(rect->pict.data[0] + pixel_count, color, run);
pixel_count += run;
} else if (!run) {
/*
* New Line. Check if correct pixels decoded, if not display
warning
* and adjust bitmap pointer to correct new line position.
*/
- if (pixel_count % sub->rects[0]->w > 0)
+ if (pixel_count % rect->w > 0)
av_log(avctx, AV_LOG_ERROR, "Decoded %d pixels, when line
should be %d pixels\n",
- pixel_count % sub->rects[0]->w, sub->rects[0]->w);
+ pixel_count % rect->w, rect->w);
line_count++;
}
}
- if (pixel_count < sub->rects[0]->w * sub->rects[0]->h) {
+ if (pixel_count < rect->w * rect->h) {
av_log(avctx, AV_LOG_ERROR, "Insufficient RLE data for subtitle\n");
return -1;
}
- av_dlog(avctx, "Pixel Count = %d, Area = %d\n", pixel_count,
sub->rects[0]->w * sub->rects[0]->h);
+ av_dlog(avctx, "Pixel Count = %d, Area = %d\n", pixel_count, rect->w *
rect->h);
return 0;
}
@@ -159,32 +228,45 @@ static int decode_rle(AVCodecContext *avctx, AVSubtitle
*sub,
* @param buf_size size of packet to process
* @todo TODO: Enable support for RLE data over multiple packets
*/
-static int parse_picture_segment(AVCodecContext *avctx,
+static int parse_object_segment(AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
PGSSubContext *ctx = avctx->priv_data;
+ PGSSubObject *object;
uint8_t sequence_desc;
unsigned int rle_bitmap_len, width, height;
+ int id;
if (buf_size <= 4)
return -1;
buf_size -= 4;
- /* skip 3 unknown bytes: Object ID (2 bytes), Version Number */
- buf += 3;
+ id = bytestream_get_be16(&buf);
+ object = find_object(id, &ctx->objects);
+ if (!object) {
+ if (ctx->objects.count >= MAX_EPOCH_OBJECTS) {
+ av_log(avctx, AV_LOG_ERROR, "Too many objects in epoch\n");
+ return -1;
+ }
+ object = &ctx->objects.object[ctx->objects.count++];
+ object->id = id;
+ }
+
+ /* skip object version number */
+ buf += 1;
/* Read the Sequence Description to determine if start of RLE data or
appended to previous RLE */
sequence_desc = bytestream_get_byte(&buf);
if (!(sequence_desc & 0x80)) {
/* Additional RLE data */
- if (buf_size > ctx->picture.rle_remaining_len)
+ if (buf_size > object->rle_remaining_len)
return -1;
- memcpy(ctx->picture.rle + ctx->picture.rle_data_len, buf, buf_size);
- ctx->picture.rle_data_len += buf_size;
- ctx->picture.rle_remaining_len -= buf_size;
+ memcpy(object->rle + object->rle_data_len, buf, buf_size);
+ object->rle_data_len += buf_size;
+ object->rle_remaining_len -= buf_size;
return 0;
}
@@ -206,17 +288,17 @@ static int parse_picture_segment(AVCodecContext *avctx,
return -1;
}
- ctx->picture.w = width;
- ctx->picture.h = height;
+ object->w = width;
+ object->h = height;
- av_fast_malloc(&ctx->picture.rle, &ctx->picture.rle_buffer_size,
rle_bitmap_len);
+ av_fast_malloc(&object->rle, &object->rle_buffer_size, rle_bitmap_len);
- if (!ctx->picture.rle)
+ if (!object->rle)
return -1;
- memcpy(ctx->picture.rle, buf, buf_size);
- ctx->picture.rle_data_len = buf_size;
- ctx->picture.rle_remaining_len = rle_bitmap_len - buf_size;
+ memcpy(object->rle, buf, buf_size);
+ object->rle_data_len = buf_size;
+ object->rle_remaining_len = rle_bitmap_len - buf_size;
return 0;
}
@@ -231,19 +313,32 @@ static int parse_picture_segment(AVCodecContext *avctx,
* @param buf pointer to the packet to process
* @param buf_size size of packet to process
*/
-static void parse_palette_segment(AVCodecContext *avctx,
+static int parse_palette_segment(AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
PGSSubContext *ctx = avctx->priv_data;
+ PGSSubPalette *palette;
const uint8_t *buf_end = buf + buf_size;
const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
int color_id;
int y, cb, cr, alpha;
int r, g, b, r_add, g_add, b_add;
+ int id;
- /* Skip two null bytes */
- buf += 2;
+ id = bytestream_get_byte(&buf);
+ palette = find_palette(id, &ctx->palettes);
+ if (!palette) {
+ if (ctx->palettes.count >= MAX_EPOCH_PALETTES) {
+ av_log(avctx, AV_LOG_ERROR, "Too many palettes in epoch\n");
+ return -1;
+ }
+ palette = &ctx->palettes.palette[ctx->palettes.count++];
+ palette->id = id;
+ }
+
+ /* Skip palette version */
+ buf += 1;
while (buf < buf_end) {
color_id = bytestream_get_byte(&buf);
@@ -258,8 +353,9 @@ static void parse_palette_segment(AVCodecContext *avctx,
av_dlog(avctx, "Color %d := (%d,%d,%d,%d)\n", color_id, r, g, b,
alpha);
/* Store color in palette */
- ctx->clut[color_id] = RGBA(r,g,b,alpha);
+ palette->clut[color_id] = RGBA(r,g,b,alpha);
}
+ return 0;
}
/**
@@ -280,8 +376,9 @@ static int parse_presentation_segment(AVCodecContext *avctx,
{
PGSSubContext *ctx = avctx->priv_data;
- int x, y, ret;
+ int i, state, ret;
+ // Video descriptor
int w = bytestream_get_be16(&buf);
int h = bytestream_get_be16(&buf);
@@ -293,49 +390,70 @@ static int parse_presentation_segment(AVCodecContext
*avctx,
if (ret < 0)
return ret;
- /* Skip 1 bytes of unknown, frame rate? */
+ /* Skip 1 bytes of unknown, frame rate */
buf++;
+ // Composition descriptor
ctx->presentation.id_number = bytestream_get_be16(&buf);
-
/*
- * Skip 3 bytes of unknown:
- * state
- * palette_update_flag (0x80),
- * palette_id_to_use,
+ * state is a 2 bit field that defines pgs epoch boundaries
+ * 00 - Normal, previously defined objects and palettes are still valid
+ * 01 - Acquisition point, previous objects and palettes can be released
+ * 10 - Epoch start, previous objects and palettes can be released
+ * 11 - Epoch continue, previous objects and palettes can be released
+ *
+ * reserved 6 bits discarded
*/
- buf += 3;
-
- ctx->presentation.object_number = bytestream_get_byte(&buf);
- ctx->presentation.composition_flag = 0;
- if (!ctx->presentation.object_number)
- return 0;
+ state = bytestream_get_byte(&buf) >> 6;
+ if (state != 0) {
+ close_objects(&ctx->objects);
+ close_palettes(&ctx->palettes);
+ }
/*
- * Skip 3 bytes of unknown:
- * object_id_ref (2 bytes),
- * window_id_ref,
+ * skip palette_update_flag (0x80),
*/
- buf += 3;
- ctx->presentation.composition_flag = bytestream_get_byte(&buf);
-
- x = bytestream_get_be16(&buf);
- y = bytestream_get_be16(&buf);
-
- /* TODO If cropping, cropping_x, cropping_y, cropping_width,
cropping_height (all 2 bytes).*/
+ buf += 1;
+ ctx->presentation.palette_id = bytestream_get_byte(&buf);
+ ctx->presentation.object_count = bytestream_get_byte(&buf);
+ if (ctx->presentation.object_count > MAX_OBJECT_REFS) {
+ av_log(avctx, AV_LOG_ERROR,
+ "Invalid number of presentation objects %d\n",
+ ctx->presentation.object_count);
+ ctx->presentation.object_count = 2;
+ }
- av_dlog(avctx, "Subtitle Placement x=%d, y=%d\n", x, y);
+ for (i = 0; i < ctx->presentation.object_count; i++)
+ {
+ ctx->presentation.objects[i].id = bytestream_get_be16(&buf);
+ ctx->presentation.objects[i].window_id = bytestream_get_byte(&buf);
+ ctx->presentation.objects[i].composition_flag =
bytestream_get_byte(&buf);
+
+ ctx->presentation.objects[i].x = bytestream_get_be16(&buf);
+ ctx->presentation.objects[i].y = bytestream_get_be16(&buf);
+
+ // If cropping
+ if (ctx->presentation.objects[i].composition_flag & 0x80) {
+ ctx->presentation.objects[i].crop_x = bytestream_get_be16(&buf);
+ ctx->presentation.objects[i].crop_y = bytestream_get_be16(&buf);
+ ctx->presentation.objects[i].crop_w = bytestream_get_be16(&buf);
+ ctx->presentation.objects[i].crop_h = bytestream_get_be16(&buf);
+ }
- if (x > avctx->width || y > avctx->height) {
- av_log(avctx, AV_LOG_ERROR, "Subtitle out of video bounds. x = %d, y =
%d, video width = %d, video height = %d.\n",
- x, y, avctx->width, avctx->height);
- x = 0; y = 0;
+ av_dlog(avctx, "Subtitle Placement x=%d, y=%d\n",
+ ctx->presentation.objects[i].x,
ctx->presentation.objects[i].y);
+
+ if (ctx->presentation.objects[i].x > avctx->width ||
+ ctx->presentation.objects[i].y > avctx->height) {
+ av_log(avctx, AV_LOG_ERROR, "Subtitle out of video bounds. x = %d,
y = %d, video width = %d, video height = %d.\n",
+ ctx->presentation.objects[i].x,
+ ctx->presentation.objects[i].y,
+ avctx->width, avctx->height);
+ ctx->presentation.objects[i].x = 0;
+ ctx->presentation.objects[i].y = 0;
+ }
}
- /* Fill in dimensions */
- ctx->presentation.x = x;
- ctx->presentation.y = y;
-
return 0;
}
@@ -359,6 +477,8 @@ static int display_end_segment(AVCodecContext *avctx, void
*data,
{
AVSubtitle *sub = data;
PGSSubContext *ctx = avctx->priv_data;
+ PGSSubPalette *palette;
+ int i;
/*
* The end display time is a timeout value and is only reached
@@ -369,43 +489,75 @@ static int display_end_segment(AVCodecContext *avctx,
void *data,
memset(sub, 0, sizeof(*sub));
sub->pts = ctx->presentation.pts;
- // Blank if last object_number was 0.
+ // Blank if last object_count was 0.
// Note that this may be wrong for more complex subtitles.
- if (!ctx->presentation.object_number)
+ if (!ctx->presentation.object_count)
return 1;
sub->start_display_time = 0;
sub->end_display_time = 20000;
sub->format = 0;
- sub->rects = av_mallocz(sizeof(*sub->rects));
- sub->rects[0] = av_mallocz(sizeof(*sub->rects[0]));
- sub->num_rects = 1;
-
- if (ctx->presentation.composition_flag & 0x40)
- sub->rects[0]->flags |= AV_SUBTITLE_FLAG_FORCED;
+ sub->num_rects = ctx->presentation.object_count;
+ sub->rects = av_mallocz(sizeof(*sub->rects) * sub->num_rects);
+ if (!sub->rects) {
+ return 0;
+ }
+ palette = find_palette(ctx->presentation.palette_id, &ctx->palettes);
+ if (!palette) {
+ // Missing palette. Should only happen with damaged streams.
+ // TODO: use a default palette?
+ av_log(avctx, AV_LOG_ERROR, "Invalid palette id %d\n",
+ ctx->presentation.palette_id);
+ sub->num_rects = 0;
+ av_freep(&sub->rects);
+ return 0;
+ }
+ for (i = 0; i < ctx->presentation.object_count; i++) {
+ PGSSubObject *object;
- sub->rects[0]->x = ctx->presentation.x;
- sub->rects[0]->y = ctx->presentation.y;
- sub->rects[0]->w = ctx->picture.w;
- sub->rects[0]->h = ctx->picture.h;
- sub->rects[0]->type = SUBTITLE_BITMAP;
+ sub->rects[i] = av_mallocz(sizeof(*sub->rects[0]));
+ if (!sub->rects[i]) {
+ sub->num_rects = i;
+ return 1;
+ }
+ sub->rects[i]->type = SUBTITLE_BITMAP;
+
+ /* Process bitmap */
+ object = find_object(ctx->presentation.objects[i].id, &ctx->objects);
+ if (!object) {
+ // Missing object. Should only happen with damaged streams.
+ av_log(avctx, AV_LOG_ERROR, "Invalid object id %d\n",
+ ctx->presentation.objects[i].id);
+ // Leaves rect empty with 0 width and height.
+ continue;
+ }
+ if (ctx->presentation.objects[i].composition_flag & 0x40)
+ sub->rects[i]->flags |= AV_SUBTITLE_FLAG_FORCED;
+
+ sub->rects[i]->x = ctx->presentation.objects[i].x;
+ sub->rects[i]->y = ctx->presentation.objects[i].y;
+ sub->rects[i]->w = object->w;
+ sub->rects[i]->h = object->h;
+
+ sub->rects[i]->pict.linesize[0] = object->w;
+
+ if (object->rle) {
+ if (object->rle_remaining_len)
+ av_log(avctx, AV_LOG_ERROR, "RLE data length %u is %u bytes
shorter than expected\n",
+ object->rle_data_len, object->rle_remaining_len);
+ if(decode_rle(avctx, sub->rects[i], object->rle,
object->rle_data_len) < 0) {
+ sub->rects[i]->w = 0;
+ sub->rects[i]->h = 0;
+ continue;
+ }
+ }
+ /* Allocate memory for colors */
+ sub->rects[i]->nb_colors = 256;
+ sub->rects[i]->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
- /* Process bitmap */
- sub->rects[0]->pict.linesize[0] = ctx->picture.w;
+ memcpy(sub->rects[i]->pict.data[1], palette->clut,
sub->rects[i]->nb_colors * sizeof(uint32_t));
- if (ctx->picture.rle) {
- if (ctx->picture.rle_remaining_len)
- av_log(avctx, AV_LOG_ERROR, "RLE data length %u is %u bytes
shorter than expected\n",
- ctx->picture.rle_data_len, ctx->picture.rle_remaining_len);
- if(decode_rle(avctx, sub, ctx->picture.rle, ctx->picture.rle_data_len)
< 0)
- return 0;
}
- /* Allocate memory for colors */
- sub->rects[0]->nb_colors = 256;
- sub->rects[0]->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
-
- memcpy(sub->rects[0]->pict.data[1], ctx->clut, sub->rects[0]->nb_colors *
sizeof(uint32_t));
-
return 1;
}
@@ -453,8 +605,8 @@ static int decode(AVCodecContext *avctx, void *data, int
*data_size,
case PALETTE_SEGMENT:
parse_palette_segment(avctx, buf, segment_length);
break;
- case PICTURE_SEGMENT:
- parse_picture_segment(avctx, buf, segment_length);
+ case OBJECT_SEGMENT:
+ parse_object_segment(avctx, buf, segment_length);
break;
case PRESENTATION_SEGMENT:
ret = parse_presentation_segment(avctx, buf, segment_length,
avpkt->pts);
--
1.9.3
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