xvid_vbr.c

自己移植的linux下的流媒体播放器原代码,支持mms协议,支持ftp和http协议.

	return(-1);

}

static int vbr_update_2pass1(void *sstate,
			     int quant,
			     int intra,
			     int header_bytes,
			     int total_bytes,
			     int kblocks,
			     int mblocks,
			     int ublocks)
			     

{

	vbr_control_t *state = sstate;

	if(state->pass1_file == NULL)
		return(-1);

	/* Writes the resulting statistics */
	fprintf(state->pass1_file, "%d %d %d %d %d %d %d\n",
		quant,
		intra,
		header_bytes,
		total_bytes,
		kblocks,
		mblocks,
		ublocks);

	/* Update vbr control state */
	if(intra) state->nb_keyframes++;
	state->nb_frames++;
	state->cur_frame++;

	return(0);
	
}

static int vbr_finish_2pass1(void *sstate)
{

	int c, i;
	vbr_control_t *state = sstate;

	if(state->pass1_file == NULL)
		return(-1);

	/* Goto to the file beginning */
	fseek(state->pass1_file, 0, SEEK_SET);

	/* Skip the version line and the empty line */
	c = i = 0;
	do {
		c = fgetc(state->pass1_file);

		if(c == EOF) return(-1);
		if(c == '\n') i++;

	}while(i < 2);

	/* Prepare to write to the stream */
	fseek( state->pass1_file, 0L, SEEK_CUR );

	/* Overwrite the frame field - safe as we have written extra spaces */
	fprintf(state->pass1_file, "# frames    : %.10d\n", state->nb_frames);

	/* Overwrite the keyframe field */
	fprintf(state->pass1_file, "# keyframes : %.10d\n",
		state->nb_keyframes);

	/* Close the file */
	if(fclose(state->pass1_file) != 0)
		return(-1);

	return(0);

}

/******************************************************************************
 * 2 pass mode - 2nd pass functions (Need to be finished)
 *****************************************************************************/

static int vbr_init_2pass2(void *sstate)
{

	FILE *f;
	int c, n, pos_firstframe, credits_frames;
	long long credits1_bytes;
	long long credits2_bytes;
	long long desired;
	long long total_bytes;
	long long itotal_bytes;
	long long start_curved;
	long long end_curved;
	double total1;
	double total2;

	vbr_control_t *state = sstate;

	/* Check the filename */
	if(state->filename == NULL || state->filename[0] == '\0')
		return(-1);

	/* Initialize safe defaults for 2pass 2 */ 
	state->pass1_file = NULL;
	state->nb_frames = 0;
	state->nb_keyframes = 0;

	/* Open the 1st pass file */
	if((f = fopen(state->filename, "r")) == NULL)
		return(-1);

	state->pass1_file = f;

	/* Get the file version and check against current version */
	fscanf(state->pass1_file, "# ASCII XviD vbr stat file version %d\n", &n);

	if(n != VBR_VERSION) {
		fclose(state->pass1_file);
		state->pass1_file = NULL;
		return(-1);
	}

	/* Skip the blank commented line */
	c = n = 0;
	do {

		c = fgetc(state->pass1_file);

		if(c == EOF) {
			fclose(state->pass1_file);
			state->pass1_file = NULL;
			return(-1);
		}

		if(c == '\n') n++;

	}while(n < 1);


	/* Get the number of frames */
	fscanf(state->pass1_file, "# frames : %d\n", &state->nb_frames);

	/* Compute the desired size */
	state->desired_size = (long long)
		(((long long)state->nb_frames * (long long)state->desired_bitrate) /
		 (state->fps * 8.0));

	/* Get the number of keyframes */
	fscanf(state->pass1_file, "# keyframes : %d\n", &state->nb_keyframes);

	/* Allocate memory space for the keyframe_location array */
	if((state->keyframe_locations
	    = (int*)malloc((state->nb_keyframes+1)*sizeof(int))) == NULL) {
		fclose(state->pass1_file);
		state->pass1_file = NULL;
		return(-1);
	}

	/* Skip the blank commented line and the colum description */
	c = n = 0;
	do {

		c = fgetc(state->pass1_file);

		if(c == EOF) {
			fclose(state->pass1_file);
			state->pass1_file = NULL;
			return(-1);
		}

		if(c == '\n') n++;

	}while(n < 2);

	/* Save position for future use */
	pos_firstframe = ftell(state->pass1_file);

	/* Read and initialize some variables */
	credits1_bytes = credits2_bytes = 0;
	total_bytes = itotal_bytes = 0;
	start_curved = end_curved = 0;
	credits_frames = 0;

	for(state->cur_frame = c = 0; state->cur_frame<state->nb_frames; state->cur_frame++) {

		int quant, keyframe, frame_hbytes, frame_bytes;
		int kblocks, mblocks, ublocks;

		fscanf(state->pass1_file, "%d %d %d %d %d %d %d\n",
		       &quant, &keyframe, &frame_hbytes, &frame_bytes,
		       &kblocks, &mblocks, &ublocks);

		/* Is the frame in the beginning credits */
		if(util_frametype(state) == FRAME_TYPE_STARTING_CREDITS) {
			credits1_bytes += frame_bytes;
			credits_frames++;
			continue;
		}

		/* Is the frame in the eding credits */
		if(util_frametype(state) == FRAME_TYPE_ENDING_CREDITS) {
			credits2_bytes += frame_bytes;
			credits_frames++;
			continue;
		}

		/* We only care about Keyframes when not in credits */
		if(keyframe) {
			itotal_bytes +=	frame_bytes + frame_bytes *
				state->keyframe_boost / 100;
			total_bytes  += frame_bytes *
				state->keyframe_boost / 100;
			state->keyframe_locations[c++] = state->cur_frame;
		}

		total_bytes += frame_bytes;		

	}

	/*
	 * Last frame is treated like an I Frame so we can dispatch overflow
	 * all other the last film segment
	 */
	state->keyframe_locations[c] = state->cur_frame;

	desired = state->desired_size;

	switch(state->credits_mode) {
	case VBR_CREDITS_MODE_QUANT :

		state->movie_curve = (double)
			(total_bytes - credits1_bytes - credits2_bytes) /
			(desired  - credits1_bytes - credits2_bytes);

		start_curved = credits1_bytes;
		end_curved   = credits2_bytes;

		break;
	case VBR_CREDITS_MODE_SIZE:

		/* start curve = (start / start desired size) */
		state->credits_start_curve = (double)
			(credits1_bytes / state->credits_start_size);

		/* end curve = (end / end desired size) */
		state->credits_end_curve = (double)
			(credits2_bytes / state->credits_end_size);

		start_curved = (long long)
			(credits1_bytes / state->credits_start_curve);

		end_curved   = (long long)
			(credits2_bytes / state->credits_end_curve);

		/* movie curve=(total-credits)/(desired_size-curved credits) */
		state->movie_curve = (double)
			(total_bytes - credits1_bytes - credits2_bytes) /
			(desired - start_curved - end_curved);

		break;
	case VBR_CREDITS_MODE_RATE:
	default:

		/* credits curve = (total/desired_size)*(100/credits_rate) */
		state->credits_start_curve = state->credits_end_curve =
			((double)total_bytes / desired) *
			((double)100 / state->credits_quant_ratio);

		start_curved =
			(long long)(credits1_bytes/state->credits_start_curve);

		end_curved   =
			(long long)(credits2_bytes/state->credits_end_curve);

		state->movie_curve = (double)
			(total_bytes - credits1_bytes - credits2_bytes) /
			(desired - start_curved - end_curved);

		break;
	}

	/*
	 * average frame size = (desired - curved credits - curved keyframes) /
	 *                      (frames - credits frames - keyframes)
	 */
	state->average_frame = (double)
		(desired - start_curved - end_curved -
		 (itotal_bytes / state->movie_curve)) /
		(state->nb_frames - util_creditsframes(state) -
		 state->nb_keyframes);

	/* Initialize alt curve parameters */
	if (state->use_alt_curve) {

		state->alt_curve_low =
			state->average_frame - state->average_frame *
			(double)(state->alt_curve_low_dist / 100.0);

		state->alt_curve_low_diff =
			state->average_frame - state->alt_curve_low;

		state->alt_curve_high =
			state->average_frame + state->average_frame *
			(double)(state->alt_curve_high_dist / 100.0);

		state->alt_curve_high_diff =
			state->alt_curve_high - state->average_frame;

		if (state->alt_curve_use_auto) {

			if (state->movie_curve > 1.0)	{

				state->alt_curve_min_rel_qual =
					(int)(100.0 - (100.0 - 100.0 / state->movie_curve) *
					      (double)state->alt_curve_auto_str / 100.0);

				if (state->alt_curve_min_rel_qual < 20)
					state->alt_curve_min_rel_qual = 20;
			}
			else {
				state->alt_curve_min_rel_qual = 100;
			}

		}

		state->alt_curve_mid_qual =
		(1.0 + (double)state->alt_curve_min_rel_qual / 100.0) / 2.0;

		state->alt_curve_qual_dev = 1.0 - state->alt_curve_mid_qual;

		if (state->alt_curve_low_dist > 100) {

			switch(state->alt_curve_type) {
			case VBR_ALT_CURVE_AGGRESIVE:
				/* Sine Curve (high aggressiveness) */
				state->alt_curve_qual_dev *=
					2.0 /
					(1.0 +  sin(DEG2RAD * (state->average_frame * 90.0 / state->alt_curve_low_diff)));

				state->alt_curve_mid_qual =
					1.0 - state->alt_curve_qual_dev *
					sin(DEG2RAD * (state->average_frame * 90.0 / state->alt_curve_low_diff));
				break;

			default:
			case VBR_ALT_CURVE_LINEAR:
				/* Linear (medium aggressiveness) */
				state->alt_curve_qual_dev *=
					2.0 /
					(1.0 + state->average_frame / state->alt_curve_low_diff);

				state->alt_curve_mid_qual =
					1.0 - state->alt_curve_qual_dev *
					state->average_frame / state->alt_curve_low_diff;

				break;

			case VBR_ALT_CURVE_SOFT:
				/* Cosine Curve (low aggressiveness) */
				state->alt_curve_qual_dev *=
					2.0 /
					(1.0 + (1.0 - cos(DEG2RAD * (state->average_frame * 90.0 / state->alt_curve_low_diff))));

				state->alt_curve_mid_qual =
					1.0 - state->alt_curve_qual_dev *
					(1.0 - cos(DEG2RAD * (state->average_frame * 90.0 / state->alt_curve_low_diff)));

				break;
			}
		}
	}

	/* Go to the first non credits frame stats line into file */
	fseek(state->pass1_file, pos_firstframe, SEEK_SET);

	/* Perform prepass to compensate for over/undersizing */
	total1 = total2 = 0.0;
	for(state->cur_frame=0; state->cur_frame<state->nb_frames; state->cur_frame++) {

		int quant, keyframe, frame_hbytes, frame_bytes;
		int kblocks, mblocks, ublocks;

		fscanf(state->pass1_file, "%d %d %d %d %d %d %d\n",
		       &quant, &keyframe, &frame_hbytes, &frame_bytes,
		       &kblocks, &mblocks, &ublocks);

		if(util_frametype(state) != FRAME_TYPE_NORMAL_MOVIE)
			continue;

		if(!keyframe) {

			double dbytes = frame_bytes / state->movie_curve;
			total1 += dbytes;

			if (state->use_alt_curve) {

				if (dbytes > state->average_frame) {

					if (dbytes >= state->alt_curve_high) {
						total2 += dbytes * (state->alt_curve_mid_qual - state->alt_curve_qual_dev);
					}
					else {

						switch(state->alt_curve_type) {
						case VBR_ALT_CURVE_AGGRESIVE:

							total2 +=
								dbytes *
								(state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								 sin(DEG2RAD * ((dbytes - state->average_frame) * 90.0 / state->alt_curve_high_diff)));
							break;
						default:
						case VBR_ALT_CURVE_LINEAR:

							total2 +=
								dbytes *
								(state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								 (dbytes - state->average_frame) / state->alt_curve_high_diff);
							break;
						case VBR_ALT_CURVE_SOFT:
							total2 +=
								dbytes *
								(state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								 (1.0 - cos(DEG2RAD * ((dbytes - state->average_frame) * 90.0 / state->alt_curve_high_diff))));
						}
					}
				}
				else {

					if (dbytes <= state->alt_curve_low) {
						total2 += dbytes;
					}
					else {

						switch(state->alt_curve_type) {
						case VBR_ALT_CURVE_AGGRESIVE:
							total2 +=
								dbytes *
								(state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								 sin(DEG2RAD * ((dbytes - state->average_frame) * 90.0 / state->alt_curve_low_diff)));
							break;
						default:
						case VBR_ALT_CURVE_LINEAR:
							total2 +=
								dbytes * 
								(state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								 (dbytes - state->average_frame) / state->alt_curve_low_diff);
							break;
						case VBR_ALT_CURVE_SOFT:
							total2 +=
								dbytes *
								(state->alt_curve_mid_qual + state->alt_curve_qual_dev *
								 (1.0 - cos(DEG2RAD * ((dbytes - state->average_frame) * 90.0 / state->alt_curve_low_diff))));
						}
					}
				}
			}
			else {
				if (dbytes > state->average_frame) {
					total2 +=
						((double)dbytes +
						 (state->average_frame - dbytes) *
						 state->curve_compression_high / 100.0);
				}
				else {
					total2 +=
						((double)dbytes +
						 (state->average_frame - dbytes) *
						 state->curve_compression_low / 100.0);
				}
			}
		}
	}
	
	state->curve_comp_scale = total1 / total2;

	if (state->use_alt_curve) {

		double curve_temp, dbytes;
		int newquant, percent;
		int oldquant = 1;

		if (state->alt_curve_use_auto_bonus_bias)
			state->alt_curve_bonus_bias = state->alt_curve_min_rel_qual;

		state->curve_bias_bonus =
			(total1 - total2) * (double)state->alt_curve_bonus_bias /
			(100.0 * (double)(state->nb_frames - util_creditsframes(state) - state->nb_keyframes));
		state->curve_comp_scale =
			((total1 - total2) * (1.0 - (double)state->alt_curve_bonus_bias / 100.0) + total2) /
			total2;


		for (n=1; n <= (int)(state->alt_curve_high*2) + 1; n++) {
			dbytes = n;
			if (dbytes > state->average_frame)
			{
				if (dbytes >= state->alt_curve_high) {
					curve_temp = dbytes * (state->alt_curve_mid_qual - state->alt_curve_qual_dev);
				}
				else {
					switch(state->alt_curve_type) {
					case VBR_ALT_CURVE_AGGRESIVE:
						curve_temp = dbytes * (state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								       sin(DEG2RAD * ((dbytes - state->average_frame) * 90.0 / state->alt_curve_high_diff)));
						break;
					default:
					case VBR_ALT_CURVE_LINEAR:
						curve_temp = dbytes * (state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								       (dbytes - state->average_frame) / state->alt_curve_high_diff);
						break;
					case VBR_ALT_CURVE_SOFT:
						curve_temp = dbytes * (state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								       (1.0 - cos(DEG2RAD * ((dbytes - state->average_frame) * 90.0 / state->alt_curve_high_diff))));
					}
				}
			}
			else {
				if (dbytes <= state->alt_curve_low) {
					curve_temp = dbytes;
				}
				else {
					switch(state->alt_curve_type) {
					case VBR_ALT_CURVE_AGGRESIVE:
						curve_temp = dbytes * (state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								       sin(DEG2RAD * ((dbytes - state->average_frame) * 90.0 / state->alt_curve_low_diff)));
						break;
					default:
					case VBR_ALT_CURVE_LINEAR:
						curve_temp = dbytes * (state->alt_curve_mid_qual - state->alt_curve_qual_dev *
								       (dbytes - state->average_frame) / state->alt_curve_low_diff);
						break;
					case VBR_ALT_CURVE_SOFT:
						curve_temp = dbytes * (state->alt_curve_mid_qual + state->alt_curve_qual_dev *
								       (1.0 - cos(DEG2RAD * ((dbytes - state->average_frame) * 90.0 / state->alt_curve_low_diff))));
					}
				}
			}

			if (state->movie_curve > 1.0)
				dbytes *= state->movie_curve;

			newquant = (int)(dbytes * 2.0 / (curve_temp * state->curve_comp_scale + state->curve_bias_bonus));
			if (newquant > 1)
			{
				if (newquant != oldquant)